High-rotating-speed washing machine inner barrel vibration reduction method based on multi-point balance supporting

Abstract

The invention relates to the technical field of mechanical balance, in particular to a high-rotating-speed washing machine inner barrel vibration reduction method based on multi-point balance supporting, which comprises the following steps: deploying a plurality of three-axis acceleration sensors in the circumferential direction of the outer wall of an inner barrel at equal intervals, performing Fourier transform on the time sequence data of each sensor, and then synthesizing the time sequence data into a vibration characteristic matrix representing the space-frequency spectrum relevance; singular value decomposition is carried out on the vibration characteristic matrix, singular vectors corresponding to the first k principal components are extracted, and a key unbalanced node coordinate set causing vibration coupling is identified according to singular vector phase distribution; applying a phase compensation block with corresponding mass at the appointed unbalanced node coordinate according to the dynamic balance parameter set through a piezoelectric ceramic micro actuator array mounted on an inner cylinder support ring; according to the invention, dynamic unbalanced torque can be effectively identified and compensated under high-speed rotation, bearing impact and cylinder polarization are reduced, and the service life of the structure is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical balancing, and in particular to a vibration reduction method for an inner drum of a high-speed washing machine based on multi-point balancing support. Background Art

[0002] With the widespread use of drum washing machines in both residential and commercial settings, users have placed higher demands on operational stability, noise control, and high-speed spin efficiency. Especially during high-speed operation, where the drum speed exceeds 1200 rpm, uneven distribution of clothing, cumulative structural tolerances, and load disturbances often cause unbalanced rotation of the drum, leading to strong vibration, increased noise, and even affecting the long-term service life of the bearing system and the machine frame.

[0003] Traditional vibration reduction technologies mainly adopt the following methods: Passive counterweight method: A fixed mass block or liquid annular capsule is preset at the edge of the inner tube to automatically form a counterweight through the centrifugal effect. However, its response capability is delayed and it cannot dynamically adjust according to the real-time imbalance state, which limits the vibration reduction effect. Mechanical shock-absorbing suspension system: Relying on a spring and damper structure to absorb the vibration caused by the eccentric movement of the inner cylinder, but the effect of suppressing high-frequency and small-amplitude vibrations is limited; Software strategy limits the speed: The spin speed is reduced before the vibration detection threshold is reached. Although this can control the vibration risk, it sacrifices the spin efficiency and overall machine performance.

[0004] Although some studies have attempted to introduce active control mechanisms (such as fuzzy control and modal filtering) for vibration compensation in recent years, there are still problems such as insufficient real-time performance, low spatial recognition accuracy, and the inability of compensation strategies to locate specific imbalance nodes. Summary of the Invention

[0005] The invention provides a vibration reduction method for the inner drum of a high-speed washing machine based on multi-point balanced support.

[0006] A method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support comprises the following steps: S1. Construction of a vibration signature matrix: Multiple triaxial acceleration sensors are deployed equidistantly around the outer wall of the inner cylinder to collect real-time three-dimensional vibration data when the rotational speed exceeds a threshold. The time series data from each sensor is Fourier transformed to form a vibration signature matrix representing spatial-spectral correlations. S2, dynamic unbalance node analysis: Perform singular value decomposition on the vibration characteristic matrix, extract the singular vectors corresponding to the first k principal components, identify the key unbalance node coordinates that cause vibration coupling based on the singular vector phase distribution, and calculate and generate a dynamic balance parameter set including counterweight position, mass and phase angle based on the speed parameter; S3, distributed mass compensation execution: through the piezoelectric ceramic micro-actuator array installed on the inner cylinder support ring, a phase compensation block of corresponding mass is applied at the specified unbalanced node coordinates according to the dynamic balance parameter set, so that the compensation torque and the original vibration torque form a 180° phase difference in the frequency domain.

[0007] Optionally, the S1 specifically includes: S11. Topology optimization deployment: Twelve sensor mounting positions are set circumferentially on the axial center plane of the welding point between the inner drum flange and the drum body of the washing machine. The mounting positions are spaced at an angle of 30 degrees. A triaxial acceleration sensor is fixed to each mounting position, and the axial sensitive direction of the sensor is parallel to the rotation axis of the inner drum. S12. Anti-interference synchronous acquisition: When the speed sensor detects that the inner drum speed is ≥1200rpm, the vibration acceleration time series data of all sensors on the x, y, and z axes are synchronously collected, and the water flow impact noise is suppressed through Hanning window filtering; S13. Space-spectral matrix synthesis: Perform fast Fourier transform on the time series data collected by each sensor, extract the energy value of the center frequency point of 1 / 3 octave in the 50-200 Hz frequency band, and construct a three-dimensional spectrum energy matrix with the row vector as the sensor number and the column vector as the combination of [center frequency × axial direction], where: The number of matrix rows corresponds to 12 spatial position numbers; The column vector dimension is m center frequencies × 3 axes; Matrix elements Indicates location No. Axial The vibration energy at the center frequency.

[0008] Optionally, the construction of the vibration characteristic matrix satisfies the following relationship: The row vectors of the matrix correspond to the spatial position numbers of the sensors, and the column vectors are the 1 / 3 octave spectrum energy values ​​of each sensor on the x, y, and z axes.

[0009] Optionally, the S2 specifically includes: S21. Extraction of main vibration modes: Perform singular value decomposition on the vibration characteristic matrix E: , Extract the left singular vectors corresponding to the first k principal components ∼ , each singular vector has a dimension of , and its components represent the relative vibration intensity weights of each spatial position; S22. Coupling node identification: Compute the phase congruency index for each singular vector component: , in For location In the The vibration phase angle at the main frequency is For the The average phase angle of the main frequency, Will The sensor location set with a score >0.95 is defined as the key unbalanced node coordinate set; S23. Dynamic parameter generation: According to the node coordinate set and real-time speed , generate the dynamic balance parameter set according to the following rules: Counterweight position: coordinates of the three nodes with the highest phase consistency index; Counterweight mass: ,in is the material density compensation coefficient, is the singular vector modulus of node j; Phase Angle: ,in The actuator response delay time.

[0010] Optionally, in S21 The value is dynamically determined based on the cumulative contribution rate of matrix eigenvalues ​​≥ 85%.

[0011] Optionally, the micro-actuator array is provided on the inner cylinder support ring and is a micro-piezoelectric actuator array arranged at equal intervals along the circumferential direction. The number of the micro-actuator array is 12, which has a one-to-one correspondence with the 12 sensor positions and is used to apply phase compensation mass at the identified unbalanced node.

[0012] Optionally, the phase compensation block is a deformable counterweight block made of shape memory alloy, and its deployment area is controlled by electric current to achieve continuous adjustment of the mass of 0.1-5g.

[0013] Optionally, the S3 specifically includes: S31. Node coordinate mapping: According to the coordinates of the counterweight position in the dynamic balance parameter set, the micro-actuator with the corresponding topological number on the support ring is activated, and the end of the actuator is provided with a shape memory alloy counterweight groove; S32. Quality-phase dual-mode control: Apply counterweight mass to the target actuator Proportional to the drive current ,in , so that the shape memory alloy expands to a specified area under the thermal effect of current, generating an accurate mass of Phase compensation block; At the same time, according to the phase angle and real-time inner barrel rotation angle , when satisfied The counterweight is triggered to pop out; S33. Frequency domain cancellation verification: After compensation, the vibration characteristic matrix is ​​collected to calculate the original vibration torque in the target frequency band of 50–200 Hz. and compensation torque The vector angle of : , like , it is determined to be a valid offset.

[0014] Optionally, the method for identifying the key unbalanced node coordinate set includes performing singular value decomposition on the vibration characteristic matrix, extracting the main modal phase angle, and identifying the key unbalanced node coordinate set that causes vibration coupling based on phase consistency index calculation. The coordinate set is used to drive the piezoelectric actuator at the corresponding position to apply phase compensation.

[0015] Optionally, in S33, the compensated vibration characteristic matrix is ​​collected in real time, and when the residual vibration energy exceeds a threshold, regeneration of the dynamic balance parameter set is triggered.

[0016] Beneficial effects of the present invention: This invention utilizes an array of equally spaced micro-piezoelectric actuators arranged on the inner cylinder support ring, combined with real-time three-axis vibration data, to construct a frequency-domain spatially coupled vibration characteristic matrix. Singular value decomposition is used to extract the primary modes, and the phase consistency index is used to accurately identify key imbalance nodes, achieving multi-point, multi-modal coordinated adjustment. This mechanism effectively identifies and compensates for dynamic unbalanced torque under high-speed rotation, reducing bearing impact and cylinder polarization, and improving structural life.

[0017] This invention proposes a dual-mode mass-phase control method that utilizes a shape memory alloy-driven counterweight slot. Under fine-tuned drive current, it outputs a compensation block with a mass error of ≤±0.05g. This method uses real-time rotation angle to determine trigger timing, ensuring that the compensation torque achieves a 180°±5° anti-phase cancellation of the original vibration torque in the frequency domain. Compared to traditional static counterweight methods, this compensation strategy can adapt to speed fluctuations and load disturbances, achieving dynamic vibration reduction with millisecond-level response, significantly reducing the structural resonance amplitude within the target frequency range (50–200Hz).

[0018] By mapping a vibration sensor array to a microactuator array, this invention establishes a spatially equivalent, phase-synchronized feedback loop. This completes the control chain from spectrum energy acquisition, modal phase decoupling, key node identification, to compensation loading. This structure features fault redundancy distribution and periodic reconfiguration capabilities, dynamically adjusting compensation schemes based on varying wash modes and drum load conditions. Its versatility and intelligent adaptability make it suitable for integrated active vibration control applications in high-end drum washing machines. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 Schematic diagram of a vibration reduction method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. It is also noted that, to provide a more detailed description, the following embodiments are best and preferred embodiments, and those skilled in the art may employ alternative methods for implementing certain known technologies. Furthermore, the accompanying drawings are intended only to provide a more detailed description of the embodiments and are not intended to limit the present invention.

[0022] It should be noted that references in the specification to "one embodiment," "an embodiment," "exemplary embodiments," "some embodiments," etc. indicate that the described embodiments may include specific features, structures, or characteristics, but not necessarily every embodiment will include such specific features, structures, or characteristics. Furthermore, when specific features, structures, or characteristics are described in conjunction with an embodiment, it is within the knowledge of persons skilled in the relevant art to implement such features, structures, or characteristics in conjunction with other embodiments (whether or not explicitly described).

[0023] In general, terms can be understood, at least in part, from their use in context. For example, depending at least in part on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending at least in part on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0024] like Figure 1As shown, a method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support includes the following steps: S1. Construction of a vibration signature matrix: Multiple triaxial acceleration sensors are deployed equidistantly around the outer wall of the inner cylinder to collect real-time three-dimensional vibration data when the rotational speed exceeds a threshold. The time series data from each sensor is Fourier transformed to form a vibration signature matrix representing spatial-spectral correlations. S2, dynamic unbalance node analysis: Perform singular value decomposition on the vibration characteristic matrix, extract the singular vectors corresponding to the first k principal components, identify the key unbalance node coordinates that cause vibration coupling based on the singular vector phase distribution, and calculate the dynamic balance parameter set including the counterweight position, mass and phase angle based on the speed parameter. S3, distributed mass compensation execution: Through the piezoelectric ceramic micro-actuator array installed on the inner cylinder support ring, a phase compensation block with corresponding mass is applied at the specified unbalanced node coordinates according to the dynamic balance parameter set, so that the compensation torque and the original vibration torque form a 180° phase difference in the frequency domain.

[0025] S1 specifically includes: S11. Topology optimization deployment: Twelve sensor mounting locations are located circumferentially along the axial center plane of the weld between the washing machine's inner drum flange and the drum, with spacing of 30°. Each location houses a triaxial accelerometer. The axial sensitivity of all sensors is parallel to the inner drum's rotational axis, ensuring accurate capture of axial vibration components. S12. Anti-interference synchronous acquisition: When the speed sensor detects that the inner drum speed meets the following conditions: , that is, activate the high speed operation monitoring mechanism. The system is not less than The sampling frequency of all sensors is synchronized to collect data on the three axes. The vibration acceleration time series data of the direction, the sampling signal first passes through the Hanning window function Windowing is performed to suppress the interference of water flow impact and ensure the effectiveness of frequency domain transformation; S13. Space-spectral matrix synthesis: Axial time series data collected for each sensor Perform a Fast Fourier Transform (FFT) on the frequency band: Internal extraction of equal proportions The energy spectrum corresponding to the octave center frequency point is used to construct a three-dimensional spectrum energy matrix: ,in, Indicates the corresponding 12 sensor spatial position numbers to ; For the indivual Octave center frequency point; Indicates the axial direction; Indicates sensor location In the Center frequency Axial The vibration energy value on Each energy value can be calculated by the following formula: , in, Indicates the sensor number, the value range , corresponding to 12 position points arranged circumferentially; Indicates the frequency band number, indicating the 1 / 3 octave center frequency points; Indicates the axial direction, the value is 、 or , represents the three measurement directions of the acceleration sensor; Indicates the A center frequency, which belongs to the 1 / 3 octave frequency point within the selected frequency band (50-200Hz); Indicates the The 1 / 3 octave bandwidth corresponding to the center frequency is calculated as ; Indicates sensor location In the axial direction The frequency domain amplitude function of the time series vibration signal collected above after FFT transformation; represents the power spectral density, i.e. the frequency Energy distribution at Indicates the integral variable, which indicates a small frequency increment and is used to adjust the bandwidth Find the total energy on top; The energy spectrum is integrated over each octave bandwidth to quantify the vibrational energy.

[0026] S2 specifically includes: S21. Extraction of main vibration modes: The vibration characteristic matrix constructed Perform singular value decomposition (SVD): , before extraction The left singular vectors corresponding to the principal components are: ,in satisfy: , Each of these , its components represent the relative vibration intensity weights of each sensor spatial position under the main mode; E represents the three-dimensional spectrum energy matrix; Represents the three parts of the singular value decomposition; Indicates the left singular vectors; Indicates the number of selected main modes, satisfying the cumulative contribution rate ≥ 85%; Indicates the singular values; S22. Coupling node identification: Calculate the position of each sensor Phase consistency index

[0027] , in, Indicates location In the The corresponding vibration phase angle at the main frequency is Indicates the The average phase angle at the main frequency; like , it is considered that there is high coherence vibration at this position, which is a key unbalanced coupling node. The key node coordinate set is obtained as follows: ; S23. Dynamic parameter generation: According to the key node coordinate set and current speed (Unit: rpm), generating a dynamic balancing parameter set.

[0028] Counterweight position: ; Take the three nodes with the largest phase consistency index as candidate matching points; Counterweight mass: ;in Indicates the material density compensation coefficient (empirical or calibrated value); Indicates the In the main mode, the position The singular vector modulus of ; Indicates location The mass of the counterweight (g); Phase Angle: ;in Indicates the actuator response delay time (seconds); Indicates location The phase angle of the counterweight (°).

[0029] S3 specifically includes: S31. Node coordinate mapping: According to the coordinates of the counterweight position in the dynamic balance parameter set , activating the micro piezoelectric actuator corresponding to the coordinate number on the inner cylinder support ring. Each actuator has a controllable counterweight slot based on shape memory alloy (SMA) at the end, which is used to eject a compensation block of a set mass.

[0030] S32. Quality-phase dual-mode control: S321.Quality Control: Apply counterweight mass to the target actuator Proportional to the drive current: ,in Represents the current quality mapping scale factor, set to A / g; Based on the thermal deformation effect of shape memory alloy, its expansion area accurately controls the mass of the counterweight: ; S322. Phase control: Real-time monitoring of the inner cylinder rotation angle , when: , that is, when the current rotation angle matches the required compensation phase angle, the trigger counterweight block pops out instantly to achieve precise phase synchronization compensation; Indicates the The target phase angle of each compensation block; S33. Frequency domain cancellation verification: After compensation is completed, re-collect the vibration characteristic matrix , and extract the original vibration torque and compensation torque in the target frequency band (50–200 Hz), which are recorded as: Original torque vector: , compensation torque vector: ; Calculate the angle between two vectors : ,in represents the phase angle between the original and compensation torques, represents the vector modulus (Euclidean norm), Represents vector dot product operation; satisfy: , it is determined that the compensation achieves effective cancellation in the frequency domain (approximately 180° phase reversal), meeting the dynamic vibration reduction requirements.

[0031] The present invention encompasses any alternatives, modifications, equivalents, and solutions that fall within the spirit and scope of the present invention. To provide a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, but those skilled in the art will be able to fully understand the present invention without these detailed descriptions. Furthermore, to avoid unnecessary confusion regarding the essence of the present invention, well-known methods, processes, procedures, components, and circuits have not been described in detail.

[0032] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A high-speed washing machine inner drum vibration reduction method based on multi-point balanced support, characterized in that: The following steps are involved: S1. Construction of a vibration signature matrix: Multiple triaxial acceleration sensors are deployed equidistantly around the outer wall of the inner cylinder to collect real-time three-dimensional vibration data when the rotational speed exceeds a threshold. The time series data from each sensor is Fourier transformed to form a vibration signature matrix representing spatial-spectral correlations. S2, dynamic unbalance node analysis: Perform singular value decomposition on the vibration characteristic matrix, extract the singular vectors corresponding to the first k principal components, identify the key unbalance node coordinates that cause vibration coupling based on the singular vector phase distribution, and calculate and generate a dynamic balance parameter set including counterweight position, mass and phase angle based on the speed parameter; S3, distributed mass compensation execution: through the piezoelectric ceramic micro-actuator array installed on the inner cylinder support ring, a phase compensation block of corresponding mass is applied at the specified unbalanced node coordinates according to the dynamic balance parameter set, so that the compensation torque and the original vibration torque form a 180° phase difference in the frequency domain.

2. A high-speed washing machine inner drum vibration reduction method based on multi-point balanced support according to claim 1, characterized in that: Said S1 specifically includes: S11. Topology optimization deployment: Twelve sensor mounting positions are set circumferentially on the axial center plane of the welding point between the inner drum flange and the drum body of the washing machine. The mounting positions are spaced at an angle of 30 degrees. A triaxial acceleration sensor is fixed to each mounting position, and the axial sensitive direction of the sensor is parallel to the rotation axis of the inner drum. S12. Anti-interference synchronous acquisition: When the speed sensor detects that the inner drum speed is ≥1200rpm, the vibration acceleration time series data of all sensors on the x, y, and z axes are synchronously collected, and the water flow impact noise is suppressed through Hanning window filtering; S13. Space-spectral matrix synthesis: Perform fast Fourier transform on the time series data collected by each sensor, extract the energy value of the center frequency point of 1 / 3 octave in the 50-200 Hz frequency band, and construct a three-dimensional spectrum energy matrix with the row vector as the sensor number and the column vector as the combination of [center frequency × axial direction], where: The number of matrix rows corresponds to 12 spatial position numbers; The column vector dimension is m center frequencies × 3 axes; Matrix elements Indicates location No. Axial The vibration energy value at the center frequency.

3. The method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support according to claim 2, characterized in that: The construction of the vibration characteristic matrix satisfies the following relationship: The row vectors of the matrix correspond to the spatial position numbers of the sensors, and the column vectors are the 1 / 3 octave spectrum energy values ​​of each sensor on the x, y, and z axes.

4. The method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support according to claim 1, characterized in that: The S2 specifically includes: S21. Extraction of main vibration modes: Perform singular value decomposition on the vibration characteristic matrix E: ， Extract the left singular vectors corresponding to the first k principal components , each singular vector has a dimension of , and its components represent the relative vibration intensity weights of each spatial position; S22. Coupling node identification: Compute the phase congruency index for each singular vector component: , in For location In the The vibration phase angle at the main frequency is For the The average phase angle of the main frequency, Will The sensor location set with a score >0.95 is defined as the key unbalanced node coordinate set; S23. Dynamic parameter generation: According to the node coordinate set and real-time speed , generate the dynamic balance parameter set according to the following rules: Counterweight position: coordinates of the three nodes with the highest phase consistency index; Counterweight mass: ,in is the material density compensation coefficient, is the singular vector modulus of node j; Phase Angle: ,in The actuator response delay time.

5. The method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support according to claim 4, characterized in that: The S21 The value is dynamically determined based on the cumulative contribution rate of matrix eigenvalues ​​≥ 85%.

6. The method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support according to claim 1, characterized in that: The micro actuator array is provided on the inner cylinder support ring and is a micro piezoelectric actuator array arranged at equal intervals along the circumferential direction. There are 12 of them, which form a one-to-one correspondence with the 12 sensor positions and are used to apply phase compensation mass at the identified unbalanced nodes.

7. The method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support according to claim 1, characterized in that: The phase compensation block is a deformable counterweight block made of shape memory alloy, and its expanded area is controlled by electric current to achieve continuous adjustment of mass from 0.1 to 5g.

8. The method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support according to claim 1, characterized in that: The S3 specifically includes: S31. Node coordinate mapping: According to the coordinates of the counterweight position in the dynamic balance parameter set, the micro-actuator with the corresponding topological number on the support ring is activated, and the end of the actuator is provided with a shape memory alloy counterweight groove; S32. Quality-phase dual-mode control: Apply counterweight mass to the target actuator Proportional to the drive current ,in , so that the shape memory alloy expands to a specified area under the thermal effect of current, generating an accurate mass of Phase compensation block; At the same time, according to the phase angle and real-time inner barrel rotation angle , when satisfied The counterweight is triggered to pop out; S33. Frequency domain cancellation verification: After compensation, the vibration characteristic matrix is ​​collected to calculate the original vibration torque in the target frequency band of 50–200 Hz. and compensation torque The vector angle of : ， like , it is determined to be a valid offset.

9. The method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support according to claim 1, characterized in that: The method for identifying the key unbalanced node coordinate set includes performing singular value decomposition on the vibration characteristic matrix, extracting the main modal phase angle, and identifying the key unbalanced node coordinate set that causes vibration coupling based on phase consistency index calculation. The coordinate set is used to drive the piezoelectric actuator at the corresponding position to apply phase compensation.

10. The method for reducing vibration of the inner drum of a high-speed washing machine based on multi-point balanced support according to claim 8, characterized in that: In the above-mentioned S33, the vibration characteristic matrix after compensation is collected in real time, and when the residual vibration energy exceeds a threshold, the dynamic balance parameter set is triggered to be regenerated.

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