CN210859141U

CN210859141U - Miniature piezoelectric pump

Info

Publication number: CN210859141U
Application number: CN201920623045.2U
Authority: CN
Inventors: 邱俊; 张秀琴; 李红元
Original assignee: Bestar Sensortech Co ltd
Current assignee: Bestar Sensortech Co ltd
Priority date: 2019-04-30
Filing date: 2019-04-30
Publication date: 2020-06-26
Anticipated expiration: 2029-04-30

Abstract

The utility model belongs to the technical field of piezoelectric pumps, in particular to a miniature piezoelectric pump, which comprises a pump body, a piezoelectric vibrator and a diaphragm, wherein the diaphragm is arranged at the bottom of the piezoelectric vibrator, the diaphragm is not contacted with the piezoelectric vibrator, the pump body at the bottom of the diaphragm is provided with two liquid inlet cavities and liquid outlet cavities which are not communicated, the liquid inlet cavity is connected with a liquid inlet pipe which is communicated with the outside, the liquid outlet cavity is connected with a liquid outlet pipe which is communicated with the outside, the diaphragm comprises a transparent outer film and an opaque bottom film at the bottom side of the outer film, laser penetrates through the outer film to burn the bottom film to realize the welding connection between the outer film and the pump body, the bottom film is provided with a movable first film tongue corresponding to the liquid outlet cavity, a movable second film tongue corresponding to the liquid inlet cavity, a first hole which is smaller than the first film tongue and enables the first film tongue to move only to one side of the liquid outlet cavity is arranged at the position corresponding to the second film tongue, the first film, the second membrane tongue is larger than the liquid inlet cavity, has small volume and high safety, and is more suitable for medical use.

Description

Miniature piezoelectric pump

Technical Field

The utility model belongs to the technical field of the piezoelectric pump, concretely relates to miniature piezoelectric pump.

Background

Piezoelectric pumps are a new type of fluid driver. The piezoelectric pump does not need an additional driving motor, but utilizes the inverse piezoelectric effect of piezoelectric ceramics to deform the piezoelectric vibrator, and then the volume change of a pump cavity is generated by the deformation to realize fluid output or the piezoelectric vibrator is utilized to generate fluctuation to transmit liquid. The piezoelectric pump consists of a piezoelectric vibrator, a diaphragm, a pump valve and a pump body. In operation, when an alternating current power supply U is applied to two ends of the piezoelectric vibrator, the piezoelectric vibrator is radially compressed under the action of an electric field, and tensile stress is generated inside the piezoelectric vibrator, so that the piezoelectric vibrator is bent and deformed. When the piezoelectric vibrator is bent in the positive direction, the piezoelectric vibrator is stretched to cause the diaphragm to change, the volume of a pump cavity is increased due to the change of the diaphragm, the pressure of fluid in the cavity is reduced, a pump valve is opened, and liquid enters the pump cavity; when the piezoelectric vibrator is bent reversely, the piezoelectric vibrator contracts, the volume of a pump cavity is reduced, the pressure of fluid in the cavity is increased, a pump valve is closed, and the liquid in the pump cavity is extruded and discharged to form smooth continuous directional flow. The piezoelectric pump has small volume and various structures, and is widely used in the fields of industry, agricultural production, biology and medicine. In applications in the medical and medical fields, a delivery system for a liquid medicine is often used, and in order to facilitate use, a further requirement is imposed on the volume of a piezoelectric pump, which is required to be as small as possible.

In addition, the diaphragm and the pump body of the existing piezoelectric pump are bonded through glue, the bonded glue is easy to be separated under the long-term soaking of the liquid medicine, so that the piezoelectric pump fails, the glue has adverse effects on safety, and the safety of the piezoelectric pump is reduced.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that to above-mentioned defect, provide a miniature piezoelectric pump, it is small, the security is high, more is applicable to medical use.

The utility model provides a technical scheme that its technical problem adopted as follows:

a miniature piezoelectric pump comprises a pump body, a piezoelectric vibrator and a diaphragm, wherein the piezoelectric vibrator and the diaphragm are arranged in the pump body, the diaphragm is arranged at the bottom of the piezoelectric vibrator, the diaphragm is not in contact with the piezoelectric vibrator, the pump body at the bottom of the diaphragm is provided with two non-communicated liquid inlet cavities and a liquid outlet cavity, the liquid inlet cavity is connected with a liquid inlet pipe leading to the outside, the liquid outlet cavity is connected with a liquid outlet pipe leading to the outside, the diaphragm comprises a transparent outer film and an opaque bottom film attached to the bottom side of the outer film, laser penetrates through the outer film to burn the bottom film to realize the welding connection between the outer film and the pump body, the bottom film is provided with a movable first film tongue corresponding to the liquid outlet cavity, a movable second film tongue corresponding to the liquid inlet cavity is arranged on the bottom film, a first hole smaller than the first film tongue and enabling the first film tongue to move only to one side of the liquid outlet cavity is arranged on the outer film corresponding to the second tongue, and the first, the second diaphragm tongue is larger than the liquid inlet cavity, the piezoelectric vibrator vibrates to drive the diaphragm to move to generate pump power which enables liquid medicine to enter the liquid outlet cavity from the liquid inlet cavity, and the thickness of the miniature piezoelectric pump is not larger than 7 mm.

Furthermore, the pump body in be equipped with a piezoelectric cavity that sets up the piezoelectric vibrator, the piezoelectric vibrator sets up in the piezoelectric cavity through the installation membrane, is equipped with the diaphragm groove of inlaying and establishing the diaphragm in the piezoelectric cavity of piezoelectric vibrator bottom, keeps parallel between diaphragm and the piezoelectric vibrator, diaphragm groove shape structure and diaphragm shape structure coincide, basement membrane and diaphragm groove cell wall welding.

Furthermore, the diaphragm is of a bilaterally symmetrical 8-shaped structure, the liquid outlet cavity and the liquid inlet cavity are bilaterally symmetrical about the middle of the diaphragm, the axis of the first hole is collinear with the axis of the liquid outlet cavity, the axis of the second through hole is collinear with the axis of the liquid inlet cavity, and the bottom surface of the second film tongue is tightly attached to the opening of the liquid inlet cavity, so that the second film tongue can only be movably opened towards the side of the second hole.

Further, the basement membrane is black.

Further, the depth of the diaphragm groove is consistent with the thickness of the diaphragm.

Furthermore, the first film tongue and the second film tongue are consistent in size and arc-shaped.

Furthermore, the first film tongue and the second film tongue are formed by cutting the film body through the cut arranged at the corresponding position on the bottom film.

Furthermore, a limiting column for limiting the opening degree of the first film tongue is arranged in the liquid outlet cavity corresponding to the bottom of the first film tongue.

Furthermore, the liquid inlet pipe and the liquid outlet pipe are both conical pipes, and the larger ends of the liquid inlet pipe and the liquid outlet pipe face the outer side of the pump body.

Furthermore, the piezoelectric cavity is provided with heat dissipation holes communicated with the inside and the outside at the upper part of the piezoelectric vibrator.

The utility model has the advantages that: by adopting the scheme, the method has the advantages that,

1) the thickness of the pump body is not more than 7mm, the volume is small, the occupied space is small, and the pump is more suitable for the medical field;

2) the diaphragm is connected with the pump body in a laser welding mode, welding consistency is good, connection is reliable, connection cannot lose efficacy when the diaphragm is soaked for a long time and temperature changes, thickness is reduced, and the diaphragm is non-toxic and high in safety;

3) the diaphragm has the functions of providing pump power and controlling the valve, a valve structure is not required to be arranged, the thickness of the pump body is reduced, the structure of the pump is simple, and the manufacturing cost is reduced;

4) the flow control consistency is good, the flow control is accurate, the response speed of the diaphragm valve control is high, the service performance of the micropump is improved, and the diaphragm valve is simple in structure and convenient to process.

Drawings

The foregoing and other objects, features, and advantages of the invention will be apparent from the following detailed description taken in conjunction with the accompanying drawings.

Fig. 1 is a schematic cross-sectional structure diagram of an embodiment of the present invention.

Fig. 2 is a schematic structural view showing a state where the bottom film and the outer film are decomposed according to an embodiment of the present invention.

Fig. 3 is a schematic structural view of a combined state of the bottom film and the outer film according to an embodiment of the present invention.

Fig. 4 is a schematic view of the diaphragm of the present invention.

Fig. 5 is another schematic view of the diaphragm of the present invention.

Wherein: 1 is a pump body, 11 is a liquid outlet cavity, 112 is a limiting column, 12 is a liquid inlet cavity, 13 is a diaphragm groove, 14 is a heat dissipation hole, 2 is a piezoelectric vibrator, 3 is a diaphragm, 31 is a bottom film, 311 is a first diaphragm tongue, 312 is a second diaphragm tongue, 32 is an outer film, 321 is a first hole, and 322 is a second hole.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings.

Example 1: referring to fig. 1, a miniature piezoelectric pump, including the pump body 1, piezoelectric vibrator 2, diaphragm 3, the pump body 1 is inside to set up the piezoelectric cavity of piezoelectric vibrator 2, diaphragm 3, there is a step surface in the piezoelectric cavity, the piezoelectric vibrator 2 sets up in the step surface place through the mounting film, the piezoelectric vibrator 2 divides the piezoelectric cavity into upper heat-dissipating area, lower working area, the upper body of the piezoelectric vibrator 2 has heat dissipating holes 14 communicating the inside and outside of piezoelectric cavity, disperse the heat produced in the work of the piezoelectric vibrator in time, keep better working condition, promote to improve the service life, the diaphragm 3 is set up in the bottom of the piezoelectric vibrator 2 parallelly, there are diaphragm grooves 13 to embed diaphragm 3 in the corresponding place of piezoelectric storehouse in the working area, the diaphragm 3 is not contacted with 2 pieces of piezoelectric vibrator, the space between diaphragm 3 and piezoelectric vibrator 2 forms the valve cavity, the depth of the diaphragm groove 13 is not smaller than the thickness of the diaphragm 3, enlarge the volume of valve pocket, the pump body 1 of diaphragm 3 bottom is equipped with two independent cylindrical feed liquor chambeies 12, go out liquid chamber 11, feed liquor chamber 12, it sets up about the middle bilateral symmetry of diaphragm 3 to go out liquid chamber 11, it is greater than feed liquor chamber 12 to go out liquid chamber 11, diaphragm 3 adopts "8" word column structure of both sides bilateral symmetry, it is corresponding, the structure in diaphragm groove is unanimous with diaphragm structure, the diaphragm of being convenient for of this kind of structure and the positioning of assembly in diaphragm groove, improve the installation accuracy of diaphragm, 1 upper portion of the pump body corresponds piezoelectric cavity opening part and is equipped with the apron, the assembly of this micropump of being convenient for.

Specifically, referring to fig. 3 and 4, the diaphragm 3 includes a black bottom film 31 and a transparent outer film 32 on the bottom film 31, the bottom end surface of the bottom film is attached to the openings of the liquid inlet chamber and the liquid outlet chamber, the size of the film body on one side of the diaphragm is larger than that of the liquid outlet chamber, a movable first film tongue 311 is disposed at the position of the bottom film 31 corresponding to the axis of the liquid outlet chamber 11, a movable second film tongue 312 is disposed at the position of the axis corresponding to the liquid inlet chamber 12, the shapes of the first film tongue 311 and the second film tongue 312 are the same, the positions of the first film tongue 311 and the second film tongue 312 are symmetrical with respect to the middle of the liquid inlet chamber 12, a first hole 321 smaller than the first film tongue 311 is disposed at the position of the outer film 32 corresponding to the first film tongue 311, a second hole 322 larger than the second film tongue 312 is disposed at the position of the outer film 32 corresponding to the second film tongue 312, the axis of the first hole 321 and the axis of the liquid outlet chamber 11 are on the same vertical line, the axis of the second hole 322 and the, because the first hole 321 is smaller than the first film tongue 311, the first film tongue 311 can only move towards the cavity of the liquid outlet cavity 12, the opening of the liquid inlet cavity 12 is smaller than the second film tongue 312, the bottom end face of the second film tongue 312 covers the opening of the top end of the liquid inlet cavity 312, so that the second film tongue 312 can only move towards the second hole 322, therefore, the first film tongue and the second film tongue form two independent one-way valves, the bottom film and the outer film form a diaphragm valve, the micro pump does not need to be provided with a traditional valve, the thickness of the micro pump is not more than 7mm, the volume of the micro pump is effectively reduced, the micro pump is more suitable for the medical field, the edge of the bottom film 31 is connected with the wall of the diaphragm groove through laser welding, the laser penetrates through the transparent outer film 32 to act on the black bottom film 31 to burn the bottom film 31, the welding connection of the bottom film 31 and the groove surface of the diaphragm groove 13 is realized, and the consistency of the diaphragm, avoiding using glue, effectively reducing the thickness of the position, promoting to reduce the whole thickness, and, the laser welding has high safety, the long-term soaking welding part of the liquid medicine can not be welded, the nontoxicity is safer and more reliable, the corresponding position on the pump body 1 is provided with a liquid outlet pipe 111 communicating the liquid outlet cavity 11 and the outside, the corresponding position on the pump body 1 is provided with a liquid inlet pipe 121 communicating the liquid inlet cavity 12 and the outside, the liquid medicine enters the liquid inlet cavity 12 from the liquid inlet pipe 121, the liquid medicine enters the liquid outlet pipe 111 from the liquid outlet cavity 11 to complete the conveying of the liquid medicine, the piezoelectric vibrator 2 vibrates to drive the diaphragm 3 to move upwards or downwards, referring to figures 4 and 5, the diaphragm moves upwards to drive the second film tongue 312 to open upwards, the liquid medicine enters the valve cavity from the liquid inlet cavity 12 to drive the first film tongue to open downwards, the liquid medicine in the valve cavity enters the liquid outlet cavity 11, realizing the quantitative pumping of the liquid medicine, the volume of the valve cavity is fixed, two independent check valves are formed at the diaphragm, the consistency of the pumping flow of the micropump is effectively improved, the cylindrical liquid outlet cavity and the liquid inlet cavity are cylindrical, the axis of the liquid outlet cavity is collinear with the axis of the first hole, the axis of the liquid inlet cavity is collinear with the axis of the second hole, the matching precision of the diaphragm and the diaphragm groove is high, the consistency of flow control is improved, the liquid inlet pipe 121 and the liquid outlet pipe 111 are of a tapered structure, the larger end of the liquid inlet pipe 121 and the liquid outlet pipe 111 faces the outer side of the pump body, the structure can improve the speed of liquid entering the liquid inlet cavity, improve the pumping efficiency, the volume of the liquid outlet cavity is larger than that of the liquid inlet cavity, the outer end of the liquid outlet pipe is large and small, the liquid outlet speed of the liquid outlet cavity is reduced, liquid medicine flows out stably from the liquid outlet cavity, the stability.

The adventitia, the basement membrane is the PET membrane, has better intensity, long service life, and the thickness of adventitia is 0.05mm, and the thickness of basement membrane is 0.1mm, and the adventitia is thin to be convenient for laser and pierces through the effect fast on the basement membrane, burns the basement membrane, realizes that quick welded connection between basement membrane and adventitia, the pump body, and laser welding's uniformity is good, and the splice welding seam width is unanimous, and the splice moves towards shape and laser trend unanimously, and welding quality is high, makes the accurate nature that improves flow control.

Specifically, the first film tongue 311 and the second film tongue 312 are formed by cutting a film body through an arc-shaped cut arranged at corresponding positions on a bottom film, the shape of the cut is the shape of the film tongue, the structure is convenient for forming the film tongue, the film tongue is positioned on the same surface with the film body after being reset, the film tongue is convenient to be matched with the film body, the film tongue can be reset rapidly, no interval is generated between the film tongue and the film body, the function of a one-way valve is exerted effectively, the distance between the diaphragm 2 and the piezoelectric vibrator 2 is 0.3mm, the upward folding and opening angle of the second film tongue is not more than 90 degrees, the length of the second film tongue is more than 0.3mm, when the second film tongue is opened, the mounting film can block the second film tongue, the overlarge folding and opening amplitude of the film tongue is avoided, the timely resetting of the second film tongue is ensured, the effect of the one-way valve is exerted fully, the axis in the liquid outlet cavity 11 is provided with a limiting column 112 which protrudes upwards and limits the opening amplitude of the first film tongue 311, the first membrane tongue 311 turns over the range of opening of rolling over downwards and receives blockking of spacing post, and opening that first membrane tongue can be nimble, and first membrane tongue can be quick resets, avoids rolling over range too big, the check valve effect of the first membrane tongue department of full play, and this micropump's thickness is little, small, and flow control is accurate, and the security is better, more is applicable to in medical science, the medical field.

Example 2: the difference between the embodiment and the embodiment 1 is that the shape of the diaphragm is a track shape, the shape of the first diaphragm tongue is a semi-circle shape, the thickness of the diaphragm is consistent with the depth of the diaphragm groove, the distance between the diaphragm and the installation film is 0.5mm, the installation film is convenient for fixing the piezoelectric vibrator, the valve cavity between the diaphragm and the installation film is of a cylindrical structure, the structure is regular, the flow control is accurate, and the use performance is improved.

The above is only the preferred embodiment of the present invention, not to the limitation of the present invention in any form, all the techniques of the present invention are substantially any simple modification and equivalent changes to the above embodiments, all falling within the protection scope of the present invention.

Claims

1. A miniature piezoelectric pump comprises a pump body, a piezoelectric vibrator inside the pump body and a diaphragm, and is characterized in that,

the diaphragm is arranged at the bottom of the piezoelectric vibrator, the diaphragm is not contacted with the piezoelectric vibrator, the pump body at the bottom of the diaphragm is provided with two liquid inlet cavities and liquid outlet cavities which are not communicated, the liquid inlet cavity is connected with a liquid inlet pipe which is communicated with the outside, the liquid outlet cavity is connected with a liquid outlet pipe which is communicated with the outside,

the diaphragm include transparent adventitia, hug closely the opaque basement membrane of adventitia bottom side, laser passes the adventitia and burns the basement membrane and realize adventitia, the welded connection between basement membrane and the pump body, basement membrane corresponds a first membrane tongue that the liquid outlet chamber department was equipped with the activity, it is equipped with the second membrane tongue of activity to correspond liquid inlet chamber department, be equipped with on the adventitia corresponding first membrane tongue and make first membrane tongue only can be to going out the first hole of liquid chamber one side motion, it is equipped with the second hole that is bigger than the second membrane tongue to correspond second membrane tongue department, first membrane tongue is less than the liquid outlet chamber, the second membrane tongue is greater than the liquid inlet chamber, the vibration of piezoelectric vibrator drives the diaphragm motion and produces the pump power that makes the liquid medicine get into the liquid outlet chamber by the liquid inlet chamber, the thickness of miniature piezoelectric pump is not more than 7 mm.

2. The miniature piezoelectric pump according to claim 1, wherein a piezoelectric cavity for accommodating the piezoelectric vibrator is provided in the pump body, the piezoelectric vibrator is accommodated in the piezoelectric cavity via an installation film, a diaphragm groove for embedding a diaphragm is provided in the piezoelectric cavity at the bottom of the piezoelectric vibrator, the diaphragm and the piezoelectric vibrator are parallel, the shape and structure of the diaphragm groove are matched with those of the diaphragm, and the bottom film is welded to the wall of the diaphragm groove.

3. A miniature piezoelectric pump according to claim 1, wherein the diaphragm is of a bilaterally symmetric 8-shaped structure, the liquid outlet chamber and the liquid inlet chamber are bilaterally symmetric about the middle of the diaphragm, the axis of the first hole is collinear with the axis of the liquid outlet chamber, the axis of the second hole is collinear with the axis of the liquid inlet chamber, and the bottom surface of the second diaphragm tongue is tightly attached to the opening of the liquid inlet chamber so that the second diaphragm tongue can only be opened to the second hole side in a movable manner.

4. A miniature piezoelectric pump as defined in claim 1, wherein the base film is black.

5. A miniature piezoelectric pump according to claim 2, wherein the depth of said diaphragm groove corresponds to the thickness of the diaphragm.

6. A miniature piezoelectric pump according to claim 1, wherein the first membrane tongue and the second membrane tongue are of uniform size, and the first membrane tongue and the second membrane tongue are both arcuate.

7. A miniature piezoelectric pump according to claim 1, wherein said first membrane flap and said second membrane flap are formed by cutting open the membrane body through respective slits formed in the base membrane.

8. A miniature piezoelectric pump according to claim 1, wherein a position-limiting post is disposed in the fluid outlet chamber corresponding to the bottom of the first diaphragm tongue for limiting the degree of opening of the first diaphragm tongue.

9. A miniature piezoelectric pump according to claim 1, wherein the inlet and outlet pipes are tapered pipes, the larger ends of the inlet and outlet pipes both facing the outside of the pump body.

10. A miniature piezoelectric pump according to claim 2, wherein the piezoelectric cavity is provided with heat dissipation holes at the upper part of the piezoelectric vibrator for communicating the inside and outside.