CN115750465A - Special-shaped piezoelectric fan and heat source structure - Google Patents

Abstract

The invention discloses a special-shaped piezoelectric fan and heat source structure, comprising: the device comprises a base and two groups of blades; the two groups of blades are distributed on the left side and the right side of the base; the blade is designed into a special-shaped structure with a large upper end and a small lower end; the small end of the blade is connected with the clamping seat; the blade is arranged on the base through the clamping seat; the output end of the driving power supply is respectively connected with the left and right groups of blades; the positive pole of the output of the driving power supply and the negative pole of the output of the driving power supply are respectively connected with the left blade and the right blade, so that the swing phase difference of the two blades is 180 degrees. The special-shaped piezoelectric fan blade is adopted, and the shape change of the blade is utilized, so that the fan blade can be used for heat dissipation in a one-dimensional space and can also be used for heat dissipation which cannot be performed by a rectangular fan in a two-dimensional space. The heat dissipation problem of direction about other than the rectangle blade fore-and-aft direction is easily solved, can solve the heat dissipation problem of direction about simultaneously as required.

Description

A special-shaped piezoelectric fan and heat source structure

technical field

The invention relates to the technical field of piezoelectric fans, and more specifically relates to a special-shaped piezoelectric fan and a heat source structure.

Background technique

The main structural components of the piezoelectric fan are composed of piezoelectric fan blades installed on an aluminum base that has been oxidized and blackened and has high insulation performance. It is composed of some parts, and its working principle is designed by using the principle of piezoelectric characteristics of piezoelectric ceramics.

In the case of electrification, piezoelectric ceramics will generate vibration and displacement, and the small mechanical vibration will be amplified to a larger blade swing by spraying noise reduction and insulating coating special-shaped steel sheets on it. Under the control of the intelligent circuit embedded in the base, the blades swing to achieve the ideal heat dissipation effect.

The current state of the art piezo fan is a rectangular piezo fan blade. For such fan blades, when multiple blades are installed through the base of the fan, the vibration of the piezoelectric fan is very large due to the superposition of the vibrations of the multiple blades. And the higher the vibration frequency of the piezoelectric fan blades, the greater the vibration. Especially when multiple piezoelectric fans are installed on the same heating module, the vibration is very powerful.

This is because the vibration source of the piezoelectric fan is multiple. In addition to the vibration superposition of multiple blades, the resonance of the blade itself, the resonance between multiple blades, the resonance between the blade and the base, the resonance between multiple fans, The resonance of the fan and the heating module, etc. This multivariate and powerful vibrating piezoelectric fan is accompanied by very loud noise. Therefore, it cannot be used in many fields, and the application scenarios are greatly limited.

In addition, some heat sources with complex structures are only suitable for heat dissipation in a one-dimensional space with a single structure due to the fan blades of a rectangular structure, and heat dissipation in a one-dimensional space in one direction of the heat source radiator on the same horizontal plane as the piezoelectric fan. When the structure of the heat source is complex and requires more than two multi-dimensional complex spaces to dissipate heat, rectangular blades cannot do it.

Contents of the invention

The invention provides a special-shaped piezoelectric fan to solve the above technical problems.

In order to achieve the above object, the present invention adopts the following technical solutions:

A special-shaped piezoelectric fan, including: a base and blades, the blades are provided with two groups; the two groups of blades are distributed on the left and right sides of the base; the blades are designed as a special-shaped structure with a large upper end and a small lower end; The end is connected with the deck; the deck, the blades are arranged on the base through the deck; the drive power supply, the output terminals of the drive power supply are respectively connected with the left and right two groups of blades; the positive pole of the drive power output and the negative pole of the drive power output They are respectively connected with the left and right two groups of blades, so that the two groups of blades swing with a phase difference of 180 degrees.

The use of special-shaped piezoelectric fan blades and the change of blade shape can be used for heat dissipation in one-dimensional space, and can also be used for heat dissipation that rectangular fans in two-dimensional space cannot do. It is easy to solve the heat dissipation problem in the front and rear directions of the rectangular blades, and can also solve the heat dissipation problem in the up and down direction according to the needs. The same special-shaped blade can also dissipate heat from two heat sources in different directions at the same time. Thus, the application surface of the piezoelectric fan is greatly broadened. In the end, the special-shaped piezoelectric fan with low vibration, large air volume and strong applicability was invented to solve these problems, which can effectively avoid large vibration and small air volume, and expand the application scenarios.

In some embodiments, the surface of the blade is coated with a noise reducing coating.

In some embodiments, the blade includes a piezoelectric ceramic sheet, a metal amplifier, and a high-strength fiber. Two piezoelectric ceramic sheets are respectively arranged on both sides of the metal amplifier. The piezoelectric ceramic sheet is divided into two polarized surfaces. It is a positive and negative pole of the piezoelectric ceramic sheet. The positive electrode of the piezoelectric ceramic sheet faces outward, and the negative electrode of the piezoelectric ceramic sheet faces inward. The negative electrode of the piezoelectric ceramic sheet is bonded with high-strength fibers to form a metal amplifier. The center of the fully symmetrical cantilever beam structure of the blade.

In some embodiments, the vane is arranged on the card seat through interference fit; the card seat is arranged on the base through interference fit.

In some embodiments, the card seat is made of elastic polymer material.

In some embodiments, the noise reduction coating is an epoxy coating.

The present application also provides a heat source structure, comprising multiple sets of the above-mentioned shaped piezoelectric fans, wherein the phases of the multiple piezoelectric fans are staggered by 90 degrees.

Description of drawings

Fig. 1 is a structural schematic diagram of a special-shaped piezoelectric fan of the present invention.

Fig. 2 is a schematic diagram of the cooperation between the card seat and the blades of a special-shaped piezoelectric fan according to the present invention.

Fig. 3 is a schematic diagram of the structure of various shaped piezoelectric fan blades.

Figure 4 is a schematic diagram of the structure of a heat source equipped with multiple groups of low-vibration, large-volume, and highly adaptable special-shaped piezoelectric fans.

In the figure: 1-metal magnifying sheet, 2-high-strength fiber, 3-piezoelectric ceramic sheet, 4-cassette, 5-base, 6-drive power supply, 7-blade, 71-upper end, 72-lower end.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below in conjunction with the drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of the application. The embodiments described below by referring to the figures are exemplary, and are intended to explain the present application, and should not be construed as limiting the present application. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

Embodiments of the present application will be described in detail below in conjunction with the accompanying drawings.

In the description of this application, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be fixed connection, or through an intermediate The media is indirectly connected, which can be the internal communication of two elements or the interaction relationship between two elements. Those of ordinary skill in the art can understand the specific meanings of the above terms in this application according to specific situations.

In the description of this application, it is to be understood that the terms "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", The orientation or positional relationship indicated by "outside" is based on the orientation or positional relationship of the drawings, and is only for the convenience of describing the application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, use a specific configuration and operation, and therefore should not be construed as limiting the application.

Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product or display comprising a sequence of steps or elements is not necessarily limited to the expressly listed Instead, other steps or elements not explicitly listed or inherent to the process, method, product or display may be included.

A special-shaped piezoelectric fan involved in the embodiment of the present application will be described in detail below with reference to FIGS. 1-4 . It should be noted that the following examples are only used to explain the present application and do not constitute a limitation to the present application.

As shown in Figure 1-3, a special-shaped piezoelectric fan includes: a base 5 and blades 7, the blades 7 are provided with two groups; two groups of blades 7 are distributed on the left and right sides of the base 5; the blades 7 are Designed as a special-shaped structure with a large upper end 71 and a lower end 72; and the small end of the blade 7 is connected to the deck 4; the deck 4, the blade 7 is arranged on the base 5 through the deck 4; the driving power supply 6, The output terminals of the drive power supply 6 are respectively connected to the left and right two groups of blades 7; the positive pole output by the drive power supply 6 and the negative pole output by the drive power supply 6 are respectively connected to the left and right two groups of blades 7, so that the two groups of blades 7 have a swing phase difference of 180 degrees.

Wherein, the blade 7 includes a piezoelectric ceramic sheet 3, a metal amplifying sheet 1, and a high-strength fiber 2, and two piezoelectric ceramic sheets 3 are respectively arranged on both sides of the metal amplifying sheet 1, and the piezoelectric ceramic sheet 3 is piezoelectric High-performance piezoelectric ceramics with constant d33 greater than 750PC/N. The tensile modulus of the high-strength fiber 2 is 36TON-40TON.

The two polarized faces of the piezoelectric ceramic sheet 3 are divided into positive and negative electrodes of the piezoelectric ceramic sheet 3. The positive electrode of the piezoelectric ceramic sheet 3 faces outward, and the negative electrode of the piezoelectric ceramic sheet 3 faces inward. The negative surface is bonded with the high-strength fiber 2 to form a blade 7 with a fully symmetrical cantilever beam structure centered on the metal amplifying sheet 1 . Then the blade 7 is clamped on the deck 4, and finally the deck 4 is pressed on the base 5 by means of interference extrusion.

The output terminals of the driving power supply 6 are respectively connected to the left and right two groups of blades 7; the positive pole output by the driving power supply 66 and the negative pole output by the driving power supply 6 are respectively connected to the left and right two groups of blades 7, and the positive pole of the ceramic sheet on one group of blades 7 is connected to the driving power supply 6 The positive pole of the output, the positive pole of the ceramic sheet on the other set of blades 7 is connected to the negative pole of the drive power supply 6, and the ground wire of the drive power supply 6 is connected to the ground wire of the blade 7, so that the swing phase of the blades 7 differs by 180 degrees. Driven by the driving power supply 6, the two sets of driving phases are opposite (phase difference 180 degrees), so that the vibrations can cancel each other out, reduce the resonance of the installation base 5, and realize the purpose of low vibration and low noise of the piezoelectric fan.

The left and right two groups of blades 7 are connected in different phases. Driven by the driving power supply 6, the two groups of driving phases are opposite, with a phase difference of 180 degrees, so as to achieve mutual cancellation of vibration, reduce the resonance of the metal base 5, and realize low vibration of the piezoelectric fan. and low noise purposes.

The piezoelectric ceramic is pasted on the high-strength fiber 2 of the metal amplifier 1, driven by the driving power supply 6, the tiny vibration of the piezoelectric ceramic 3 is amplified by the metal amplifier 1 to the vibration of the ceramic, and the metal amplifier 1 It forms a relatively large swing like a cattail fan, which disturbs the air around the heat source, forms the exchange of cold and hot air, and achieves the purpose of heat dissipation.

In order to further reduce noise, the deck 4 is made of elastic polymer materials, such as plastic, nylon, plastic and the like. The structure of the card holder 4 has also been innovated. The section of the card holder 4 is a trapezoid with a large upper end and a smaller lower end. There is a through cavity in the card holder 4 along the length direction. The cavity is used for later glue filling. After the glue is poured, the glue will also absorb part of the low-frequency vibration. The top of the holder 4 is provided with a limiting slot communicating with the cavity for installing the blade 7 . Select a polymer material with a certain elasticity on the material of the deck 4, and use the elasticity of the material of the deck 4 to absorb part of the low-frequency vibration through mechanical filtering; secondly, in the structural design of the deck 4, it is designed to have a large upper end, a small lower end, and a middle The hollow micro-spring structure absorbs the vibration from the blade 7 to the greatest extent and reduces the resonance of the metal base 5; it has a certain effect of vibration reduction and noise reduction.

In addition to using materials including piezoelectric ceramic sheets 3 and high-strength fibers 2, the key is to use special-shaped structural steel sheets sprayed with noise reduction and insulating coatings on them, and special-shaped piezoelectric fan blades 7 in a cantilever beam structure. First, the surface of the blade 7 is coated with a noise-reducing coating to reduce the noise caused by friction between the blade 7 and the air. The insulating coating can be an epoxy resin coating, which are commonly used epoxy resin coatings in the prior art.

Secondly, utilizing the characteristics of the special-shaped blade 7, the blade 7 is designed such that the upper end 71 is larger and the lower end 72 is smaller. The design of the lower end 72 is small in size, the piezoelectric ceramic sheet 3 used is small in size, and the vibration energy output by the piezoelectric ceramic will also become smaller. The piezoelectric fan is composed of a plurality of blades 7, and the plurality of blades 7 are combined. Compared with the rectangular blades 7, the vibration of the piezoelectric fan as a whole is greatly reduced, and the resonance between the plurality of blades 7 is also reduced. In addition, the size of the upper end 71 of the fan blade 7 is large, and the mass of the upper end 71 of the blade 7 is large. As a result, the swing frequency of the fan blades 7 with the same length and the special-shaped blades 7 is reduced, the swing range of the blades 7 is increased, and the output air volume is also large. Simultaneously, the frequency of the fan blade 7 is low, and the vibration will also be low. As shown in FIG. 3 , the blade 7 can be designed in many forms, as long as the upper end 71 is larger and the lower end 72 is smaller.

In order to solve the superposition of the vibration of multiple blades on the same base, the blades of a fan are divided into left and right groups, and a certain distance is left for the middle fan. When driving, the phase difference of the fan blades of the left and right groups is 180 degrees. The two resistance fan blades on the same base vibrate due to opposite phases, and the vibrations cancel each other out, further reducing the fan vibration.

As shown in Figure 4, it is a heat source structure equipped with multiple groups of special-shaped piezoelectric fans with low vibration, large air volume and strong applicability. In order to solve the problem that on the same heat source module, the swing frequency of the two fan blades is the same, which causes resonance between the two fans, and the test makes abnormal noise. In order to avoid regular humming caused by resonance, the phase difference of the two piezoelectric fans is 90 degrees.

When a fan drive is at a high potential, that is when the fan blades oscillate the most, and that's when the vibration is greatest. If the two fans are driven with a phase difference of 90 degrees, the latter fan starts to start when the former piezoelectric fan is at a high potential.

At the beginning, the piezoelectric fan started after the start did not work before the piezoelectric fan started at the highest potential, and the static piezoelectric fan did not generate any vibration, so the two groups of piezoelectric fans would not resonate with each other. Because the two fans have a phase difference of 90 degrees, when the previous piezoelectric fan is going from high potential to low potential, the latter piezoelectric fan is also going from low potential to high potential. At this time, the high and low potentials of the two piezoelectric fans meet, The vibrations of each other cancel each other out. During the operation of the two fans, there will always be one rise and one fall, which well avoids the resonance of the two fans, thereby further reducing the vibration and noise of the piezoelectric fan.

The beneficial effects of a special-shaped piezoelectric fan provided by this application include but are not limited to:

The beneficial effect that the present invention has compared with prior art is:

(1) A special-shaped piezoelectric fan with low vibration, large air volume and strong applicability is used to avoid the piezoelectric fan in the prior art, which has large vibration and low air volume, and is suitable for small-scale problems. The invention adopts the special-shaped steel sheet sprayed with noise reduction and insulating coating on it, so as to overcome the shortcoming of the rectangular structure in the prior art. The piezoelectric ceramic sheet used in the blade of rectangular structure has a large volume, and the vibration energy of the ceramic is large. The special-shaped steel sheet with noise reduction and insulating coating is sprayed on it. The width of the fixed end of the piezoelectric fan blade is narrow. The width of the free end in front of the piezoelectric fan blade is increased, and the blade swing frequency is low. As the frequency of swinging of the blades decreases, the vibration of the fan itself is also small, and the vibration of the fan is reduced.

(2) From the perspective of heat dissipation effect, the larger the air volume output by the piezoelectric fan, the better the heat dissipation effect. The air volume is proportional to the cross-sectional area of the air outlet of the fan, and the larger the cross-section of the air outlet, the greater the air volume. Because the front of the blade of the special-shaped piezoelectric fan is wide, it is as wide as the rectangular fan blade. However, because the upper end of the special-shaped blade is wide and the lower end is small, and the quality of the upper end is heavy. For blades of the same length, the blade with a heavy upper end has a lower swing frequency, so the swing amplitude of the special-shaped blade is greater than that of the rectangular blade. In the case of the same width at the upper end, the greater the swing of the blades, the greater the cross-sectional area of the air outlet, and the greater the air volume. With rectangular blades, the air volume at the outlet is determined by the width of the blades. If the heat source has a special structure, the shape of the upper end of the blade can be designed according to the different structure, which not only solves the heat dissipation problem of the special structure, but also increases the air volume output by the fan with the increase of the width of the upper end of the blade. bigger. At the same time, the vibration of the ceramic sheet is reduced, the natural vibration of the blade is reduced, and the vibration and noise of the entire piezoelectric fan are also reduced.

(3) In order to solve the superposition of the vibration of multiple blades on the same base in order to solve the problem of piezoelectric fans, the original group of fan blades is divided into two groups of left and right, and the huge amount between the two groups of blades is opened to prevent the two groups of blades from Interference between adjacent blades due to opposing fans. When driving, the phase difference between the two groups of fan blades is 180 degrees. The blades of the two resistance fans on the same base swing in opposite directions, the vibrations between the two groups of blades cancel each other out, and the vibration of the piezoelectric fan is effectively reduced.

(4) In order to solve the resonance sound caused by the use of multiple sets of piezoelectric fans in the same heating module. When the blades of multiple piezoelectric fans installed on the same heating module have the same swing frequency, the multiple piezoelectric fans will resonate with each other and emit regular buzzing sounds. The method of staggering the driving phases of multiple groups of adjacent piezoelectric fans by 90 degrees avoids the resonance generated by the two groups of fans and reduces the noise.

(5) The change of the blade shape of the piezoelectric fan enables the blade to be flexible and changeable, adapting to the heat dissipation of different structures, and can be closer to the heat source, expanding from one-dimensional space to two-dimensional space for heat dissipation. Easily solve the multi-dimensional heat dissipation requirements of complex heat source structures, and expand the application of piezoelectric fans.

(6) It has very good practicability, can be produced in batches, and has good economic and social effects.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (7)

1. A special-shaped piezoelectric fan, characterized in that, comprising: a base and There are two groups of blades; the two groups of blades are distributed on the left and right sides of the base; the blades are designed as a special-shaped structure with a large upper end and a smaller lower end; and the small end of the blade is connected to the card seat; a card seat, the blade is arranged on the base through the card seat; The drive power supply, the output terminals of the drive power supply are respectively connected to the left and right two sets of blades; the positive pole of the drive power output and the negative pole of the drive power output are respectively connected to the left and right two sets of blades, so that the two sets of blades swing with a phase difference of 180 degrees. 2. A special-shaped piezoelectric fan according to claim 1, characterized in that the surface of the blade is coated with a noise-reducing coating. 3. A special-shaped piezoelectric fan according to claim 1, wherein the blades include piezoelectric ceramic sheets, metal amplifiers, and high-strength fibers, and two piezoelectric ceramic sheets are respectively arranged on both sides of the metal amplifiers. side, the polarized two faces of the piezoelectric ceramic sheet are divided into positive and negative electrodes of the piezoelectric ceramic sheet, the positive electrode of the piezoelectric ceramic sheet faces outward, and the negative electrode of the piezoelectric ceramic sheet faces inward. The high-strength fibers are bonded together to form a blade with a fully symmetrical cantilever beam structure centered on the metal magnifying sheet. 4 . The special-shaped piezoelectric fan according to claim 1 , wherein the blades are arranged on the card seat through interference fit; and the card seat is arranged on the base through interference fit. 5 . 5. A special-shaped piezoelectric fan according to any one of claims 1-4, characterized in that the holder is made of elastic polymer material. 6 . The special-shaped piezoelectric fan according to claim 2 , wherein the noise reduction coating is an epoxy resin coating. 7. A heat source structure, characterized in that it comprises multiple sets of the special-shaped piezoelectric fans according to any one of claims 1-6, wherein the phases of the multiple piezoelectric fans are staggered by 90 degrees.

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