CN113013319B - Low-frequency active vibration suppression system based on integrated structure - Google Patents

Abstract

The invention provides a low-frequency active vibration suppression system based on an integrated structure, which comprises a vibration suppression function device and an active vibration suppression system device, wherein the vibration suppression function device structure comprises a piezoelectric fiber composite layer, two metal electrode layers respectively covering the top surface and the bottom surface of the piezoelectric fiber composite layer and two packaging layers for packaging the piezoelectric fiber composite layer and the metal electrode layers into a whole; the invention aims to solve the problem of low vibration suppression efficiency in a low-frequency vibration range in the prior art, provides a design idea based on an integrated structure, and through the embedded design of a vibration suppression function device part, the vibration suppression function device can be embedded into a vibration mechanism through a packaging layer in a conformal manner by virtue of the flexible characteristic of a piezoelectric fiber composite layer when in use, so that the vibration loss in the process of transmitting the vibration energy of the vibration mechanism to the vibration suppression function device is obviously reduced, and the mechanical coupling efficiency of the vibration suppression function device and the vibration mechanism is greatly improved.

Description

A Low Frequency Active Vibration Suppression System Based on Integrated Structure

technical field

The invention relates to the field of mechanical vibration suppression, in particular to a low-frequency active vibration suppression system based on an integrated structure.

Background technique

Vibration is a common natural phenomenon in people's daily life, especially in engineering technology, such as the vibration of the bridge body due to the erosion of waves; the vibration of railroad tracks due to the rapid friction of trains; ; Vibration of lathes and molds due to friction, etc. Generally speaking, vibrations in nature are divided into favorable vibrations and unfavorable vibrations, and unfavorable vibrations often cause some damage, such as the accuracy of precision instruments is greatly reduced due to unfavorable vibrations; components appear due to long-term vibrations. Fatigue damage, resulting in greatly reduced service life of the device; some vibrations may also cause destructive deformation of the structure, such as bridge body collapse due to resonance, aircraft tail due to flutter often cause serious accidents; in addition, in people's daily life, some The noise generated by equipment vibration will cause a lot of troubles in people's life. These unfavorable vibrations are often undesirable, so how to effectively control these unfavorable vibrations needs to be solved urgently.

According to the amount of external energy required for vibration control, researchers divide it into three categories: passive vibration control, active vibration control and semi-active vibration control. Passive vibration control mainly reduces the vibration of the structure through vibration absorption or vibration isolation, without providing additional energy, its applicable frequency range is narrow, and it lacks environmental adaptability. When the structure is disturbed by a broadband with high uncertainty, Passive vibration control has significant limitations. Active vibration control is to introduce the driving force opposite to the vibration direction of the main structure as part of the vibration suppression element, and then control the structure through different algorithms to make it have better response characteristics to disturbances. This method is flexible , can adapt to the vibration of wide frequency band, is favored by people, and has a wider application prospect. When actively controlling the vibration of a structure, the vibration signal must be fed back to the control system, and then the control system will respond accordingly to control the structure, which requires the introduction of vibration suppression components with both sensing and driving capabilities.

The intelligent materials constituting the vibration suppression components are the product of the development of modern technology. The emergence of intelligent materials such as shape memory alloy (SMA), piezoelectric materials, electrorheological materials and giant magnetostrictive materials has made the active vibration control technology develop rapidly. Among them, piezoelectric materials are a kind of intelligent materials that realize the mutual conversion between mechanical energy and electrical energy. This type of material has the characteristics of strong drive, outstanding sensing ability, and fast response speed, and has been widely used in the fields of drive and sensing. . Therefore, the active vibration control of the main structure using piezoelectric materials as vibration suppression elements has great application prospects.

The traditional piezoelectric active vibration suppression system has the problem of mechanical coupling efficiency between the vibration source mechanism and the piezoelectric vibration suppression device. Since both of them exist independently, they are generally solved by simple local chemical bonding, local welding and physical fastening, etc. Therefore, the adverse vibration generated by the vibration source mechanism will more or less have the problems of vibration loss and low coupling efficiency when it is transmitted to the piezoelectric vibration suppression device.

Contents of the invention

In order to solve the problem of low vibration suppression efficiency in the low-frequency vibration range in the prior art, the purpose of the present invention is to provide a low-frequency active vibration suppression system based on an integrated structure. With the flexible characteristics of the piezoelectric fiber composite layer, the The device is conformally embedded into the vibration mechanism through the packaging layer, which significantly reduces the vibration loss in the process of the vibration energy of the vibration mechanism being transmitted to the vibration suppression function device, and greatly improves the mechanical coupling efficiency between the vibration suppression function device and the vibration mechanism.

The present invention is achieved by adopting the following technical solutions:

A low-frequency active vibration suppression system based on an integrated structure, including a vibration suppression function device and an active vibration suppression system device;

The vibration-suppressing functional device includes a piezoelectric fiber composite layer, two metal electrode layers and two encapsulation layers, wherein the two metal electrode layers respectively cover the top surface and the bottom surface of the piezoelectric fiber composite layer, and the piezoelectric fiber composite layer layer and two metal electrode layers constitute a piezoelectric fiber composite sheet, and the two encapsulation layers encapsulate the piezoelectric fiber composite layer and the metal electrode layer from both sides of the piezoelectric fiber composite sheet;

The piezoelectric fiber composite layer includes a plurality of piezoelectric ceramic fibers parallel to each other and a plurality of epoxy resin fibers respectively filled and arranged between every two adjacent piezoelectric ceramic fibers, each piezoelectric ceramic fiber, each Epoxy fibers are arranged alternately in the piezoelectric fiber composite layer.

Further, in order to realize low-frequency active vibration suppression applications, the active vibration suppression system device includes an electrically connected signal generator, a high-voltage amplifier, and a controller;

Wherein, the controller controls the signal generator to generate an AC signal, and the high-voltage amplifier amplifies the AC signal to drive the vibration suppression functional device.

Further, the thickness of the piezoelectric fiber composite layer is 0.1mm-3mm; in the piezoelectric fiber composite layer, the width of each piezoelectric ceramic fiber is 0.01mm-0.1mm, and each epoxy resin The width of the fiber is 0.01mm-0.1mm.

Further, the piezoelectric fiber composite layer is made by arranging large-scale piezoelectric ceramic sheets with a thickness of T=0.1mm-3mm in parallel at equal intervals d=0.01mm-0.1mm, and filling and injecting epoxy into the gaps thereof. The composite material block formed after the resin adhesive is cured is precision mechanically cut along the direction perpendicular to the plane of the piezoelectric ceramic sheet to form a fiber sheet. The cutting thickness T1 is controlled at 0.1mm-3mm, and the cutting length is not limited. It can be based on The actual needs are controlled by adjusting the length of the piezoelectric ceramic sheet.

Further, the material of the piezoelectric ceramic sheet used to form the piezoelectric fiber composite layer, that is, the material of the piezoelectric ceramic fiber can be lead zirconate titanate (PTZ), potassium sodium niobate (KNN), barium titanate (BT ) and other series of ceramic materials.

Further, the metal electrode layer is sputtered onto the top/bottom surface of the piezoelectric fiber composite layer by means of ion sputtering, and its material includes common conductive metal materials such as gold, silver, copper, platinum, etc., and the metal electrode layer The thickness T2 can be precisely controlled within the range of 10nm-1000nm by adjusting the sputtering time, and the area covered by the metal electrode layer is the top/bottom surface of the piezoelectric fiber composite layer.

Further, the vibration-suppressing function device also includes two metal lead-out foil strips respectively connected to the two metal electrode layers, and the metal electrode layers on both sides are respectively drawn out from the packaging layer through two metal lead-out foil strips, and the metal lead-out foil strips It can be any commercially available conductive metal foil.

Further, the material of the packaging layer is a glass fiber reinforced plastic sheet; the glass fiber reinforced plastic sheet used for the packaging layer is specifically formed by curing a single-layer or multi-layer glass fiber cloth soaked with an epoxy resin adhesive. Among them, the thickness T3 of the glass fiber reinforced plastic sheet using a single layer of glass fiber cloth is 0.1 mm. In the actual application process, the thickness T4 of the glass fiber reinforced plastic sheet can be adjusted by adjusting the number n of layers of glass fiber cloth, T4=n×T3.

Further, the preparation process of the vibration-suppressing functional device is a component process of an integrated structure, and the component process of the integrated structure is: first, the bottom surface of the piezoelectric fiber composite material sheet with a thickness of T5=T1+2×T2 Attached to the semi-cured FRP sheet with a thickness of T4, using the semi-cured epoxy resin adhesive on the FRP sheet to realize the bonding and curing of the metal electrode layer and the piezoelectric fiber composite layer; secondly, in order to realize the packaging of the vibration suppression function device, Afterwards, another semi-cured FRP sheet with a thickness of T4 needs to be attached to the top surface of the piezoelectric fiber composite sheet with a thickness of T5=T1+2×T2 and cured; among them, the two metal lead-out foils must be guaranteed to be from The inside of the package body extends out.

Further, the low-frequency active vibration suppression system based on the integrated structure has a resonant frequency f in the range of 10 Hz-50 Hz, and a low-frequency vibration suppression efficiency e in the range of 50%-90%.

Further, the working mode of the vibration suppressing functional device mainly adopts the d31 mode of the piezoelectric material, and also has part of the d33 mode of the piezoelectric material.

Compared with prior art, the beneficial effect of the present invention is:

(1) Most of the traditional anti-vibration devices are partially chemically bonded, partially welded or physically fastened to the vibration mechanism to realize the mechanical coupling function between the two. The super-strong bonding ability realizes the full bonding of the vibration suppression function device and the vibration mechanism, especially for the vibration mechanism made of glass fiber reinforced plastic, and can also realize a fully embedded structure mode, and finally realize efficient mechanical coupling, which greatly enhances the vibration suppression efficiency.

(2) Due to the characteristics of the ultra-thin piezoelectric fiber composite layer and fiber flexibility, in the application of the curved surface vibration mechanism, the vibration suppression functional device involved in the present invention can also realize the conformal function of the low-frequency active vibration suppression system and the vibration mechanism, Compared with the traditional anti-vibration function device, the application range is wider.

Description of drawings

Fig. 1 is a structural analysis diagram of a vibration suppression functional device in a low-frequency active vibration suppression system based on an integrated structure related to the present invention;

Fig. 2 is the physical figure of the active vibration suppression system device and the performance test platform of the low-frequency active vibration suppression system based on the integrated structure according to the embodiment of the present invention;

Fig. 3 is the physical diagram of the vibration suppression function device in the form of a cantilever beam vibration suppression plate;

Fig. 4 is the cross-sectional metallographic diagram of the piezoelectric fiber composite sheet in Fig. 3;

Fig. 5 is the cantilever beam resonant frequency test chart of the cantilever beam type anti-vibration function device in Fig. 3;

FIG. 6 is a test diagram of the driving performance of the cantilever beam type anti-vibration functional device in FIG. 3 .

Detailed ways

The technical solutions in the embodiments of the present invention will be described in detail below in combination with the drawings in the patent embodiments of the present invention. Apparently, the embodiment described in this implementation mode is only a general case of the content contained in the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without other creative work other than the claims of the present invention fall within the protection scope of the present invention.

The invention provides a low-frequency active vibration suppression system based on an integrated structure, which includes two parts: a vibration suppression function device and an active vibration suppression system device. Wherein, as shown in FIG. 1, the vibration suppression function device includes a piezoelectric fiber composite layer 1, two layers of metal electrode layers 2 covering the top and bottom surfaces of the piezoelectric fiber composite layer 1 respectively, and two layers of piezoelectric fiber composite layers. Layer 1 and metal electrode layer 2 are packaged into one packaging layer 3, wherein the piezoelectric fiber composite layer 1 and the two metal electrode layers 2 constitute a piezoelectric fiber composite material sheet, and the two packaging layers 3 are separated from the compressed The electrical fiber composite sheet is encapsulated on both sides. In addition to the above-mentioned anti-vibration functional devices, in order to realize low-frequency active anti-vibration applications, the active anti-vibration system device needs to include a signal generator 6 , a high-voltage amplifier 7 and a controller 8 that are electrically connected.

Specifically, the piezoelectric fiber composite layer 1 includes a plurality of piezoelectric ceramic fibers 11 spaced parallel to each other and a plurality of epoxy resin fibers 12 respectively filled and arranged between every two adjacent piezoelectric ceramic fibers 11, each Piezoelectric ceramic fibers 11 and each epoxy resin fiber 12 are alternately arranged in the first layer of piezoelectric fiber composite layer.

Specifically, the thickness of the piezoelectric fiber composite layer 1 is 0.1mm-3mm; in the piezoelectric fiber composite layer 1, the width of each piezoelectric ceramic fiber 11 is 0.01mm-0.1mm, each The width of the epoxy resin fiber 12 is 0.01mm-0.1mm.

Specifically, the specific preparation process of the piezoelectric fiber composite layer 1 is as follows: a plurality of piezoelectric ceramic sheets are arranged in parallel at equal intervals, wherein the thickness of the piezoelectric ceramic sheets is T=0.01mm-0.1mm, and two adjacent piezoelectric ceramic sheets are pressed The distance between the electric ceramic sheets is d=0.01mm-0.1mm; then the epoxy resin adhesive is filled and injected into the gaps of the multiple piezoelectric ceramic sheets arranged in parallel, and the composite material block is obtained after curing, and then along the vertical direction The direction of the plane of the electroceramic sheet is cut out of the fiber sheet from the composite material block. The cutting thickness is T1 controlled at 0.1mm-3mm, and the cutting length is not limited. It can be controlled by adjusting the length of the piezoelectric ceramic sheet according to actual needs. The fiber The sheets can then be used as piezoelectric fiber composite layers.

Specifically, the material of the piezoelectric ceramic sheet used to form the piezoelectric fiber composite layer, that is, the material of the piezoelectric ceramic fiber, may be a series of ceramic materials such as PTZ, KNN, and BT.

Specifically, the metal electrode layer 2 is sputtered onto the top/bottom surface of the piezoelectric fiber composite layer 1 by means of ion sputtering, and its material includes common conductive metal materials such as gold, silver, copper, platinum, etc., and its thickness T2 It can be accurately controlled within the range of 10nm-1000nm by adjusting the sputtering time. The area covered by the metal electrode layer 2 is the top/bottom surface of the piezoelectric fiber composite layer 1; (not shown) leads, and the metal lead-out chaff can be any commercially available conductive metal foil.

Specifically, one end of the metal lead-out chaff is connected to the metal electrode layer 2 , and the other end extends from the encapsulation layer 3 .

Specifically, the material of the encapsulation layer 3 is a glass fiber reinforced plastic sheet; the preparation process of the glass fiber reinforced plastic sheet used as the encapsulation layer 3 is as follows: after soaking single-layer or multi-layer glass fiber cloth in epoxy resin epoxy resin adhesive, , taken out and solidified; wherein, the thickness T3 of the glass fiber reinforced plastic sheet using a single layer of glass fiber cloth is 0.1mm. T3.

Specifically, the preparation process of the vibration-suppressing functional device is a component process of an integrated structure, and the component process of the integrated structure is: first, the bottom surface of the piezoelectric fiber composite material sheet with a thickness of T5=T1+2×T2 Attached to the semi-cured glass fiber reinforced plastic sheet with a thickness of T4, using the semi-cured epoxy resin adhesive on the glass fiber reinforced plastic sheet to realize the bonding and curing of the metal electrode layer 2 and the piezoelectric fiber composite layer 1; secondly, in order to realize the vibration suppression function device After that, another semi-cured FRP sheet with a thickness of T4 needs to be attached to the top surface of the piezoelectric fiber composite sheet with a thickness of T5=T1+2×T2, and cured; among them, the two metal lead-out foil strips must Guaranteed to extend from inside the package. Thus, the main functional parts of the low-frequency active vibration suppression device based on the integrated structure involved in the present invention can be formed.

Fig. 3 is the physical diagram of the vibration suppression function device in the form of a cantilever beam vibration suppression sheet; Fig. 4 is a cross-sectional metallographic diagram of the piezoelectric fiber composite sheet in Fig. 3; wherein the cantilever beam vibration suppression sheet in Fig. 3 is specially used for Intrinsic performance test of the vibration-suppressing functional device; as can be seen from the cross-sectional metallographic diagram shown in Figure 4, in the piezoelectric fiber composite layer, the epoxy resin fiber is in close contact with the piezoelectric ceramic fiber, and no air bubbles are generated. , the metal electrode layer formed by sputtering adheres to the piezoelectric fiber composite layer without falling off; it shows that the vibration suppression function device material has good compactness.

In order to test the low-frequency vibration suppression performance of a low-frequency active vibration suppression system based on an integrated structure disclosed in the present invention, the following examples use the vibration suppression function device of the cantilever beam vibration suppression plate in Figure 3 and build a set of performance for it testing platform. As shown in Figure 2, the performance test platform includes a signal generator 6, a high-voltage amplifier 7, a controller 8, an excitation table 9, and an MT3 laser displacement sensor 10, wherein the signal generator 6, the high-voltage amplifier 7, and the controller 8 constitute A complete set of active vibration suppression system devices, signal generator 6, high-voltage amplifier 7, controller 8, excitation table 9 and MT3 laser displacement sensor 10 constitute a performance testing platform. Wherein, the controller 8 controls the signal generator 6 to generate an AC signal, and the high-voltage amplifier 7 amplifies the AC signal to drive the vibration suppression functional device; the excitation table 9 is used to generate vibration, and the MT3 laser displacement sensor 10 is used It is used to detect the end displacement of the cantilever beam vibration suppression piece. The specific test process is as follows:

The first step is to conduct polarization treatment on the piezoelectric fiber composite layer: place the prepared cantilever beam vibration suppression sheet in silicone oil, at room temperature, the polarization electric field is 2-3kV/mm, and the polarization time is about 10- 20min.

The second step is to determine the resonant frequency of the cantilever beam vibration suppression piece: fix the cantilever beam vibration suppression piece on the excitation table 9, apply an electrical frequency sweep of 1-50 Hz to the cantilever beam vibration suppression piece, when the electrical frequency and its natural frequency When they are consistent, the cantilever beam vibration suppression piece will resonate, and at this time its deformation reaches the maximum value, thereby obtaining the natural frequency (resonant frequency) of the cantilever beam vibration suppression piece itself. It can be seen from Fig. 5 that the displacement of the tip of the cantilever beam vibration suppression plate reaches the maximum at a frequency of about 24 Hz, so the resonance frequency of the cantilever beam vibration suppression plate is about 24 Hz.

The third step is to use the performance test platform shown in Figure 2 to test the driving performance of the low-frequency active vibration suppression system based on the integrated structure. The test results can be seen in Figure 6. The plate is fixed on the excitation table 9, and the driving performance is tested by applying a driving voltage to the cantilever beam vibration suppression plate. At a resonant frequency of 24 Hz, with the increase of the driving voltage, the tip displacement of the cantilever beam vibration suppression plate gradually increases. When the voltage is 600V, the tip displacement of the piezoelectric cantilever reaches the maximum value of 0.177mm.

The fourth step is to use the performance test platform shown in Figure 2 to test the vibration suppression performance of the low-frequency active vibration suppression system based on the integrated structure. On stage 9, under no driving voltage, the cantilever beam vibration suppression plate will maintain the sinusoidal motion with the largest vibration amplitude at 24Hz. When the driving voltage is applied, the piezoelectric phase in the piezoelectric cantilever beam generates driving force and deformation vibration due to the electromechanical coupling effect, and superimposes with the vibration wave generated by the excitation table 9 to achieve the effect of reducing the amplitude , when the driving voltage with an electric frequency of 24Hz and a voltage strength of 600V is applied, the amplitude of the piezoelectric cantilever beam is reduced by about 52.8%, and the vibration suppression effect is remarkable.

It will be obvious to a person skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in any other specific form without departing from the spirit or essential characteristics of the invention. Therefore, this embodiment is only an exemplary case, and is non-limiting. The scope of the present invention is defined by the appended claims rather than the above description, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims (9)

1. A low-frequency active vibration suppression system based on an integrated structure, characterized in that it includes a vibration suppression function device and an active vibration suppression system device; The vibration-suppressing functional device includes a piezoelectric fiber composite layer, two metal electrode layers and two encapsulation layers, wherein the two metal electrode layers respectively cover the top surface and the bottom surface of the piezoelectric fiber composite layer, and the piezoelectric fiber composite layer layer and two metal electrode layers constitute a piezoelectric fiber composite sheet, and the two encapsulation layers encapsulate the piezoelectric fiber composite layer and the metal electrode layer from both sides of the piezoelectric fiber composite sheet; The piezoelectric fiber composite layer includes a plurality of piezoelectric ceramic fibers parallel to each other and a plurality of epoxy resin fibers respectively filled and arranged between every two adjacent piezoelectric ceramic fibers, each piezoelectric ceramic fiber, each Epoxy resin fibers are alternately arranged in the piezoelectric fiber composite layer; The material of the encapsulation layer is a glass fiber reinforced plastic sheet; the encapsulation layer is specifically formed by solidifying after infiltration of a single-layer or multi-layer glass fiber cloth by an epoxy resin adhesive; The vibration-suppressing functional device is bonded and connected with the vibration mechanism through the encapsulation layer. 2. The low-frequency active vibration suppression system based on an integrated structure according to claim 1, wherein the thickness of the piezoelectric fiber composite layer is 0.1mm-3mm; In the piezoelectric fiber composite layer, the width of each piezoelectric ceramic fiber is 0.01mm-0.1mm, and the width of each epoxy resin fiber is 0.01mm-0.1mm. 3. The low-frequency active vibration suppression system based on an integrated structure according to any one of claims 1-2, wherein the preparation process of the piezoelectric fiber composite layer is: multiple piezoelectric ceramic sheets, etc. The spacing is arranged in parallel, wherein the thickness of the piezoelectric ceramic sheets is 0.01mm-0.1mm, and the distance between two adjacent piezoelectric ceramic sheets is 0.01mm-0.1mm; then in the gaps between the multiple piezoelectric ceramic sheets arranged in parallel Filling and injecting epoxy resin adhesive, after curing, a composite material block is obtained, and then a fiber sheet is cut from the composite material block along a direction perpendicular to the plane of the piezoelectric ceramic sheet, and the cutting thickness of the fiber sheet is 0.1mm-3mm, to obtain Piezoelectric fiber composite layer. 4. The low-frequency active vibration suppression system based on an integrated structure according to claim 1, characterized in that, in the piezoelectric fiber composite layer, the material of the piezoelectric ceramic fiber is a lead zirconate titanate series ceramic material , Potassium sodium niobate series ceramic materials, and one or more of barium titanate series ceramic materials. 5. The low-frequency active vibration suppression system based on an integrated structure according to claim 1, wherein the thickness of the metal electrode layer is 10nm-1000nm, and the material of the metal electrode layer is gold, silver, copper, One or more of platinum; the metal electrode layer is formed by ion sputtering on the surface of the piezoelectric fiber composite layer. 6. The low-frequency active vibration suppression system based on an integrated structure according to claim 1, wherein the vibration suppression functional device also includes two metal lead-out chaff strips respectively connected to the two metal electrode layers, and the metal One end of the lead-out chaff is connected to the metal electrode layer, and the other end extends from the encapsulation layer. 7. The low-frequency active vibration suppression system based on the integrated structure according to claim 1, wherein the preparation process of the vibration suppression functional device is a component process of the integrated structure, and the component process of the integrated structure is: First, attach the bottom surface of the piezoelectric fiber composite sheet to the semi-cured FRP sheet, and use the semi-cured epoxy resin adhesive on the FRP sheet to realize the bonding and curing of the metal electrode layer and the piezoelectric fiber composite layer; secondly, in order to realize For the packaging of the device with vibration suppression function, another semi-cured glass fiber reinforced plastic sheet is attached to the top surface of the piezoelectric fiber composite sheet and cured. 8. The low-frequency active vibration suppression system based on an integrated structure according to claim 1, wherein the resonance frequency range is 10Hz-50Hz, and the low-frequency vibration suppression efficiency range is 50%-90%; The working mode of the vibration-suppressing functional device has both the d31 mode of the piezoelectric material and the d33 mode of a part of the piezoelectric material. 9. The low-frequency active vibration suppression system based on an integrated structure according to claim 1, wherein the active vibration suppression system device includes an electrically connected signal generator, a high-voltage amplifier and a controller; The controller controls the signal generator to generate an AC signal, and the high-voltage amplifier amplifies the AC signal to drive the vibration suppression functional device.

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