Traveling wave type piezoelectric micropump and electronic equipment

Abstract

The invention relates to the technical field of pumps, in particular to a traveling wave type piezoelectric micropump and electronic equipment.The traveling wave type piezoelectric micropump comprises a supporting shell, and a rectangular groove extending in the first direction is formed in the supporting shell; the elastic supporting body is fixedly arranged on the groove bottom of the rectangular groove in the first direction; the traveling wave elastic body is supported on the elastic supporting body, the traveling wave elastic body is located in the rectangular groove, and the traveling wave elastic body and the rectangular groove form a rectangular channel; the plurality of first piezoelectric elements are arranged at one end, deviating from the elastic support body, of the traveling wave elastic body at intervals along the first direction; and the plurality of second piezoelectric elements are arranged at one end, deviating from the elastic supporting body, of the traveling wave elastic body at intervals along the first direction. The thickness of the traveling wave type piezoelectric micropump can be reduced, so that the thickness of electronic equipment is reduced, and the user experience is improved.

Description

Technical Field

[0001] The invention relates to the technical field of pumps, and in particular to a traveling wave piezoelectric micro pump and electronic equipment. Background Art

[0002] Piezoelectric ceramic micropumps are actuators that utilize the inverse piezoelectric effect of piezoelectric ceramics. They have the advantages of simple structure, low power consumption, high reliability, high precision, and immunity to electromagnetic interference. Piezoelectric ceramic micropumps are widely used in precision instruments, medical treatment, biopharmaceuticals and other fields.

[0003] At present, when consumer electronic devices such as mobile phones are working, the chip generates a lot of heat, and it is necessary to dissipate heat in time to reduce the temperature of the chip and ensure the working function of the electronic device. In order to quickly reduce the temperature of the chip, attempts have been made to use piezoelectric ceramic micropumps to perform air / liquid cooling on the chip. However, since the piezoelectric ceramic micropump is thick, the electronic device after installing the piezoelectric ceramic micropump is also thick, making it difficult to achieve a lightweight design, resulting in a poor user experience.

[0004] Therefore, a traveling wave piezoelectric micropump and electronic equipment are needed to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a traveling wave piezoelectric micropump and an electronic device, which can reduce the thickness, thereby reducing the thickness of the electronic device and improving the user experience.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] Traveling wave piezoelectric micropump, comprising:

[0008] A supporting shell, wherein the supporting shell is provided with a rectangular groove extending along a first direction;

[0009] An elastic support body, fixedly disposed on the bottom of the rectangular groove along the first direction;

[0010] A traveling wave elastic body, supported on the elastic support body, and the traveling wave elastic body is located in the rectangular groove, and the traveling wave elastic body and the rectangular groove form a rectangular channel;

[0011] A plurality of first piezoelectric elements are arranged at intervals along the first direction at one end of the traveling wave elastic body away from the elastic support body, and the electrode polarities of adjacent first piezoelectric elements are opposite, and the first piezoelectric elements are driven by sinusoidal electrical signals;

[0012] A plurality of second piezoelectric elements are spaced apart along the first direction at one end of the traveling wave elastomer away from the elastic support body, and the second piezoelectric elements are arranged in the same column as the first piezoelectric elements, the electrode polarities of adjacent second piezoelectric elements are opposite, the adjacent first piezoelectric elements are spaced apart from the second piezoelectric elements, and the electrode polarities of the two are the same, and the second piezoelectric elements are driven by a cosine electrical signal.

[0013] In some embodiments, a ratio of a distance L from a first piece of the first piezoelectric element to a last piece of the second piezoelectric element along the first direction to a length W of the first piezoelectric element or the second piezoelectric element satisfies: 2≤L / W≤4.

[0014] In some embodiments, a thickness h of the first piezoelectric element and the second piezoelectric element is ≤ 0.2 mm.

[0015] In some embodiments, the spacing between adjacent first piezoelectric elements and second piezoelectric elements is nλ / 4, where n is a positive integer greater than zero, and λ is the wavelength of the electrical signal.

[0016] In some embodiments, the distance between adjacent first piezoelectric elements and second piezoelectric elements is λ / 4.

[0017] In some embodiments, the first piezoelectric element and the second piezoelectric element are formed by sintering a single layer or multiple layers of piezoelectric ceramics.

[0018] In some embodiments, the traveling wave elastomer is made of brass, stainless steel, glass fiber or carbon fiber.

[0019] In some embodiments, the first piezoelectric element and / or the second piezoelectric element are fixed on the traveling wave elastomer by adhesive.

[0020] In some embodiments, a first piezoelectric ceramic sheet is provided on the traveling wave elastomer, and a plurality of the first piezoelectric elements are formed on the first piezoelectric ceramic sheet by screen printing, and / or a second piezoelectric ceramic sheet is provided on the traveling wave elastomer, and a plurality of the second piezoelectric elements are formed on the second piezoelectric ceramic sheet by screen printing.

[0021] An electronic device comprises a chip and the traveling wave type piezoelectric micro pump as described above, wherein the traveling wave type piezoelectric micro pump is used to drive a cooling medium to cool and dissipate heat for the chip.

[0022] Beneficial effects of the present invention:

[0023] The present invention provides a traveling wave type piezoelectric micro pump, in which a rectangular groove extending along a first direction is provided on a supporting shell, a traveling wave elastic body is arranged on the supporting body through an elastic supporting body, and the traveling wave elastic body and the rectangular groove form a rectangular channel. A plurality of first piezoelectric elements and a plurality of second piezoelectric elements are arranged along the first direction at one end of the traveling wave elastic body away from the elastic supporting body, the electrode polarities of adjacent first piezoelectric elements are opposite, the motor polarities of adjacent second piezoelectric elements are opposite, and adjacent first piezoelectric elements are arranged at intervals with adjacent second piezoelectric elements. The plurality of first piezoelectric elements are driven by sine electric signals, and the plurality of second piezoelectric elements are driven by cosine electric signals. Since the adjacent first piezoelectric elements and second piezoelectric elements are arranged at intervals, the vibrations of the first piezoelectric elements and the second piezoelectric elements driven by the electric signal do not interfere with each other. The vibrations of the first piezoelectric elements and the second piezoelectric elements driven by the electric signal are transmitted to the traveling wave elastic body, so that the vibration driving medium of the traveling wave elastic body flows unidirectionally from the rectangular channel. Since the traveling wave elastomer and the elastic support body are both arranged in the rectangular groove, the rectangular groove can be used to effectively accommodate the traveling wave elastomer and the elastic support body, so that the thickness of the traveling wave piezoelectric micropump can be reduced. Therefore, when the traveling wave piezoelectric micropump is installed on an electronic device, the thickness of the electronic device can be reduced, thereby improving the user experience.

[0024] An electronic device provided by the present invention comprises a chip and the traveling wave piezoelectric micropump as described above. Since the traveling wave piezoelectric micropump has a small thickness, the thickness of the electronic device on which the traveling wave piezoelectric micropump is installed is reduced, thereby improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0026] Figure 1 Schematic diagram of a traveling wave piezoelectric micropump of the present invention;

[0027] Figure 2 It is a schematic diagram of electrical signal input of a first piezoelectric element and a second piezoelectric element in a traveling wave piezoelectric micropump of the present invention;

[0028] Figure 3 It is a schematic diagram of the electrode polarity arrangement of the first piezoelectric element and the second piezoelectric element in a traveling wave piezoelectric micropump of the present invention.

[0029] In the figure:

[0030] 1. Support shell; 11. Rectangular channel; 2. Elastic support body; 3. Traveling wave elastic body; 4. First piezoelectric element; 5. Second piezoelectric element. DETAILED DESCRIPTION

[0031] Before any embodiments of the application are explained in detail, it is to be understood that the application is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the above drawings.

[0032] In this application, the terms "comprises", "includes", "has" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of more restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device that includes the element.

[0033] In the present application, the terms "connect", "combine", "couple", and "install" may refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, direct connection refers to two parts or components being connected together without the need for an intermediate piece, and indirect connection refers to two parts or components being connected to at least one intermediate piece respectively, and the two parts or components being connected via the intermediate piece. In addition, "connect" and "couple" are not limited to physical or mechanical connections or couplings, and may include electrical connections or couplings.

[0034] In this application, it will be understood by those skilled in the art that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0035] In the present application, the terms "upper", "lower", "left", "right", "front", "back" and other directional words are described based on the orientation and positional relationship shown in the accompanying drawings, and should not be understood as limiting the embodiments of the present application. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element. It should also be understood that directional words such as upper side, lower side, left side, right side, front side, back side, etc. not only represent the positive orientation, but can also be understood as the lateral orientation. For example, the bottom can include directly below, lower left, lower right, lower front, and lower back, etc.

[0036] When electronic devices are working, the chip will generate a lot of heat. In order to effectively cool the chip, a piezoelectric ceramic micropump is usually arranged in the electronic device to drive the cooling medium to circulate and cool the chip. However, the existing piezoelectric ceramic micropump is relatively thick, which makes it impossible to design electronic devices to be thin and light.

[0037] In order to solve the above problems, the thickness of the piezoelectric micropump is reduced, thereby reducing the thickness of the electronic device and improving the user experience, such as Figure 1-Figure 3 As shown, the present invention provides a traveling wave piezoelectric micro pump, which comprises a supporting housing 1 , an elastic supporting body 2 , a traveling wave elastic body 3 , a plurality of first piezoelectric elements 4 and a plurality of second piezoelectric elements 5 .

[0038] Among them, a rectangular groove extending along the first direction is provided on the support shell 1. The elastic support body 2 is fixedly arranged on the bottom of the rectangular groove along the first direction. The traveling wave elastic body 3 is supported on the elastic support body 2, and the traveling wave elastic body 3 is located in the rectangular groove, and the traveling wave elastic body 3 and the rectangular groove form a rectangular channel 11. A plurality of first piezoelectric elements 4 are arranged at intervals along the first direction at one end of the traveling wave elastic body 3 away from the elastic support body 2, and the electrode polarities of adjacent first piezoelectric elements 4 are opposite, and the first piezoelectric elements 4 are driven by sinusoidal electrical signals. A plurality of second piezoelectric elements 5 are arranged at intervals along the first direction at one end of the traveling wave elastic body 3 away from the elastic support body 2, and the second piezoelectric elements 5 are arranged in the same column as the first piezoelectric elements 4, the electrode polarities of adjacent second piezoelectric elements 5 are opposite, the adjacent first piezoelectric elements 4 and the second piezoelectric elements 5 are arranged at intervals, and the electrode polarities of the two are the same, and the second piezoelectric elements 5 are driven by cosine electrical signals.

[0039] The traveling wave elastic body 3 is arranged on the supporting body through the elastic supporting body 2, and the traveling wave elastic body 3 and the rectangular groove form a rectangular channel 11. By setting the elastic supporting body 2, the traveling wave elastic body 3 can be supported, so that the traveling wave elastic body 3 and the rectangular groove form a rectangular channel 11. Since the adjacent first piezoelectric element 4 and the second piezoelectric element 5 are arranged at intervals, the vibrations of the first piezoelectric element 4 and the second piezoelectric element 5 driven by the electric signal do not interfere with each other. And the vibrations of the first piezoelectric element 4 and the second piezoelectric element 5 driven by the electric signal are transmitted to the traveling wave elastic body 3, so that the traveling wave elastic body 3 vibration driving medium flows unidirectionally from the rectangular channel 11. Since the traveling wave elastic body 3 and the elastic supporting body 2 are both arranged in the rectangular groove, the traveling wave elastic body 3 and the elastic supporting body 2 are effectively accommodated by the rectangular groove, which can reduce the thickness of the traveling wave type piezoelectric micro pump, thereby reducing the thickness of the electronic device after being installed on the electronic device, and improving the user experience.

[0040] In some embodiments, the ratio of the distance L from the first piezoelectric element 4 to the last second piezoelectric element 5 along the first direction to the length W of the first piezoelectric element 4 or the second piezoelectric element 5 satisfies: 2≤L / W≤4. Through the above definition, the traveling wave piezoelectric micropump is formed into a long strip, which facilitates smooth vibration after the sine electric signal is connected to the first piezoelectric element 4 and the cosine electric signal is connected to the second piezoelectric element 5, so that the medium can flow unidirectionally from the rectangular channel 11.

[0041] In some embodiments, the thickness of the first piezoelectric element 4 and the second piezoelectric element 5 is h≤0.2 mm. By limiting the thickness of the first piezoelectric element 4 and the second piezoelectric element 5, on the one hand, after the electrical signal is connected, the first piezoelectric element 4 and the second piezoelectric element 5 can effectively vibrate, thereby driving the traveling wave elastic body 3 to vibrate and driving the medium to flow in one direction. On the other hand, it can avoid the first piezoelectric element 4 and the second piezoelectric element 5 being too thick, thereby further reducing the thickness of the traveling wave piezoelectric micropump.

[0042] In some embodiments, the spacing between adjacent first piezoelectric elements 4 and second piezoelectric elements 5 is nλ / 4, where n is a positive integer greater than zero, and λ is the wavelength of the electrical signal. By isolating the adjacent first piezoelectric elements 4 and second piezoelectric elements, mutual interference of vibrations between the first piezoelectric elements 4 and the second piezoelectric elements 5 can be avoided.

[0043] In some embodiments, the spacing between adjacent first piezoelectric elements 4 and second piezoelectric elements 5 is λ / 4. Through experimental tests, when the spacing between adjacent first piezoelectric elements 4 and second piezoelectric elements 5 is an integer multiple of λ / 4, the effect of the first piezoelectric elements 4 and second piezoelectric elements 5 not affecting each other is better. Among them, the spacing between adjacent first piezoelectric elements 4 and second piezoelectric elements 5 is λ / 4, which has the best effect.

[0044] In some embodiments, the first piezoelectric element 4 and the second piezoelectric element 5 are formed by sintering a single layer or a multilayer piezoelectric ceramic. The material of the first piezoelectric element 4 and the second piezoelectric element 5 can be PZT, KNN or BNT. Piezoelectric ceramic is a material that can convert electrical energy into mechanical energy. Among piezoelectric ceramics, PZT, KNN or BNT are widely used. When selecting piezoelectric ceramic materials, it is necessary to decide according to the specific application scenario and performance requirements. For example, if you are concerned about environmental protection and sustainability, you can choose lead-free piezoelectric ceramics such as KNN and BNT. If you pursue high performance and stability, you may choose PZT. Specifically, you can choose according to the application scenario, and there are no too many restrictions here.

[0045] In some embodiments, the elastic support body 2 is made of silicone or a polymer material with a certain flexibility. The traveling wave elastomer 3 is connected to the supporting shell 1 through the elastic support body 2. The traveling wave elastomer 3 is effectively supported by setting the elastic support body 2, so that the traveling wave elastomer 3 and the bottom of the rectangular groove are spaced to form a rectangular channel 11, which is convenient for the flow of the medium. The elastic support body 2 can play a vibration-absorbing role to prevent the supporting shell 1 from vibrating. Moreover, the elastic support body 2 has a certain viscosity, which can effectively realize the connection between the traveling wave elastomer 3 and the supporting shell 1.

[0046] In some embodiments, the material of the traveling wave elastic body 3 is brass, stainless steel, glass fiber or carbon fiber. Specifically, according to the application of the traveling wave piezoelectric micropump, a suitable material can be selected, and no excessive restrictions are made here.

[0047] In some embodiments, the first piezoelectric element 4 and / or the second piezoelectric element 5 are fixed on the traveling wave elastic body 3 by adhesive. The first piezoelectric element 4 and / or the second piezoelectric element 5 are designed as a single body, and then arranged at intervals on the traveling wave elastic body 3 according to the electrode polarity. In the above manner, the number of the first piezoelectric element 4 and the second piezoelectric element 5 can be set according to actual needs.

[0048] In some embodiments, the width of the first piezoelectric element 4 and the second piezoelectric element 5 can be designed to be 1 / 2 of the electrical signal wavelength. The first piezoelectric element 4 and the second piezoelectric element 5 can be designed as a single body, and arranged as required on the traveling wave elastomer 3. The first piezoelectric element 4 can have the same width for easy manufacturing. Of course, different widths can also be used, and there is no excessive restriction here.

[0049] In some embodiments, a first piezoelectric ceramic sheet is provided on the traveling wave elastic body 3, and a plurality of first piezoelectric elements 4 are formed on the first piezoelectric ceramic sheet by screen printing, and / or a second piezoelectric ceramic sheet is provided on the traveling wave elastic body 3, and a plurality of second piezoelectric elements 5 are formed on the second piezoelectric ceramic sheet by screen printing. By adopting the screen printing method, a plurality of first piezoelectric elements 4 and a plurality of second piezoelectric elements 5 can be quickly generated, which is convenient for manufacturing.

[0050] In some embodiments, the first piezoelectric element 4 and the second piezoelectric element 5 are used symmetrically and driven by u=sin(ωt) electrical signal and u=cos(ωt) electrical signal at the same time. If the medium needs to turn, one side can be inverted.

[0051] This embodiment also provides an electronic device, including a chip and the above-mentioned traveling wave piezoelectric micropump, the traveling wave piezoelectric micropump is used to drive a cooling medium to cool the chip. Since the traveling wave piezoelectric micropump is relatively thin, the thickness of the electronic device equipped with the traveling wave piezoelectric micropump is reduced, thereby improving the user experience.

[0052] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A traveling wave piezoelectric micropump, characterized in that: include: A supporting shell (1), wherein the supporting shell (1) is provided with a rectangular groove extending along a first direction; An elastic support body (2) is fixedly arranged on the bottom of the rectangular groove along the first direction; A traveling wave elastic body (3) is supported on the elastic support body (2), and the traveling wave elastic body (3) is located in the rectangular groove, and the traveling wave elastic body (3) and the rectangular groove form a rectangular channel (11); A plurality of first piezoelectric elements (4) are arranged at intervals along the first direction at one end of the traveling wave elastic body (3) away from the elastic support body (2), and the electrode polarities of adjacent first piezoelectric elements (4) are opposite, and the first piezoelectric elements (4) are driven by a sinusoidal electrical signal; A plurality of second piezoelectric elements (5) are arranged at intervals along the first direction at one end of the traveling wave elastomer (3) away from the elastic support body (2), and the second piezoelectric elements (5) are arranged in the same column as the first piezoelectric elements (4), the electrode polarities of adjacent second piezoelectric elements (5) are opposite, and the adjacent first piezoelectric elements (4) and second piezoelectric elements (5) are arranged at intervals and the electrode polarities of the two are the same, and the second piezoelectric elements (5) are driven by cosine electrical signals.

2. The traveling wave piezoelectric micropump according to claim 1, characterized in that: The ratio between the distance L from the first piezoelectric element (4) to the last piezoelectric element (5) along the first direction and the length W of the first piezoelectric element (4) or the second piezoelectric element (5) satisfies: 2≤L / W≤4.

3. The traveling wave piezoelectric micropump according to claim 1, characterized in that: The thickness h of the first piezoelectric element (4) and the second piezoelectric element (5) is ≤ 0.2 mm.

4. The traveling wave piezoelectric micropump according to claim 1, characterized in that: The distance between adjacent first piezoelectric elements (4) and second piezoelectric elements (5) is nλ / 4, where n is a positive integer greater than zero, and λ is the wavelength of the electrical signal.

5. The traveling wave piezoelectric micropump according to claim 4, characterized in that: The distance between the adjacent first piezoelectric elements (4) and the second piezoelectric elements (5) is λ / 4.

6. The traveling wave piezoelectric micropump according to claim 1, characterized in that: The first piezoelectric element (4) and the second piezoelectric element (5) are formed by sintering a single layer or multiple layers of piezoelectric ceramics.

7. The traveling wave piezoelectric micropump according to claim 1, characterized in that: The material of the traveling wave elastomer (3) is brass, stainless steel, glass fiber or carbon fiber.

8. The traveling wave piezoelectric micropump according to claim 1, characterized in that: The first piezoelectric element (4) and / or the second piezoelectric element (5) are fixed on the traveling wave elastomer (3) by means of adhesive.

9. The traveling wave piezoelectric micropump according to claim 1, characterized in that: The traveling wave elastomer (3) is provided with a first piezoelectric ceramic sheet, on which a plurality of the first piezoelectric elements (4) are formed by screen printing, and / or the traveling wave elastomer (3) is provided with a second piezoelectric ceramic sheet, on which a plurality of the second piezoelectric elements (5) are formed by screen printing.

10. An electronic device, characterized in that The invention comprises a chip and a traveling wave piezoelectric micropump as claimed in any one of claims 1 to 9, wherein the traveling wave piezoelectric micropump is used to drive a cooling medium to cool and dissipate heat for the chip.

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