阅读说明：本技术 洗衣机烘干风道的复合吸声装置、复合吸声方法及洗衣机 (Composite sound absorption device and method for drying air duct of washing machine and washing machine ) 是由 许�鹏 汪随 于 2019-11-21 设计创作，主要内容包括：本发明提供一种用于洗衣机烘干风道的复合吸声装置,包括：至少一组对应设置的主动吸声结构和被动吸声结构,所述被动吸声结构,用于被动吸收烘干风道中的噪音,包括在烘干风道侧壁上向外凸起形成的腔体和封盖在所述腔体的腔口处的微穿孔板；所述主动吸声结构用于对经被动吸声结构吸声后的噪音进行主动消音,包括控制器、扬声器、第一声音传感器和第二声音传感器,其中所述扬声器设置在所述腔体的腔顶,所述第一声音传感器设置在所述腔体之前,所述第二声音传感器设置在所述腔体的侧壁,所述控制器根据所述第一声音传感器测得的第一电信号和第二声音传感器测得的第二电信号,控制所述扬声器产生次级声场平衡经所述微穿孔板后噪音的声压。(The invention provides a composite sound absorption device for a drying air duct of a washing machine, which comprises: the passive sound absorption structure is used for passively absorbing noise in the drying air channel and comprises a cavity formed by outward bulges on the side wall of the drying air channel and a micro-perforated plate covering the opening of the cavity; the active sound absorption structure is used for actively silencing noise after sound absorption through the passive sound absorption structure, and comprises a controller, a loudspeaker, a first sound sensor and a second sound sensor, wherein the loudspeaker is arranged at the top of a cavity of the cavity, the first sound sensor is arranged before the cavity, the second sound sensor is arranged on the side wall of the cavity, the controller is used for controlling the loudspeaker to generate secondary sound field balance channel according to a first electric signal measured by the first sound sensor and a second electric signal measured by the second sound sensor.)

1. A composite sound absorption device for a drying air duct of a washing machine is characterized by comprising: at least one group of active sound absorption structure and passive sound absorption structure which are correspondingly arranged,

the passive sound absorption structure is used for passively absorbing noise in the drying air duct and comprises a cavity formed by protruding outwards on the side wall of the drying air duct and a micro-perforated plate covering the opening of the cavity;

the active sound absorption structure is used for actively silencing the noise absorbed by the passive sound absorption structure and comprises a controller, a loudspeaker, a first sound sensor and a second sound sensor,

the loudspeaker is arranged at the top of the cavity, the first sound sensor is arranged in front of the cavity, the second sound sensor is arranged on the side wall of the cavity, and the controller controls the loudspeaker to generate secondary sound field balance passing through the sound pressure of the noise behind the micro-perforated plate according to a first electric signal measured by the first sound sensor and a second electric signal measured by the second sound sensor.

2. The composite sound absorption device for the drying air duct of the washing machine as claimed in claim 1, wherein the composite sound absorption device comprises N sets of correspondingly arranged active sound absorption structures and passive sound absorption structures which are connected in sequence,

in the N active sound absorption structures, except that the first sound sensor and the second sound sensor are arranged in the first group of active sound absorption structures, the active sound absorption structures in other groups are only provided with the second sound sensor, and N is a positive integer larger than 1.

3. The composite sound absorbing device for a washing machine as claimed in claim 2, wherein the N sets of the active and passive sound absorbing structures disposed in correspondence are arranged along a wind path direction.

4. The composite sound absorbing device for a drying duct of a washing machine as claimed in claim 3, wherein the controller modifies the corresponding speaker according to the second sound sensor in the nth active sound absorbing structure, where N e N.

5. The composite sound absorbing device for the drying duct of the washing machine as claimed in any one of claims 1 to 4, wherein the second sound sensor is disposed at the center of the sidewall of the cavity.

6. The composite sound absorption device for the drying air duct of the washing machine as claimed in claim 5, wherein the microperforated panel is provided with a plurality of through holes, wherein the thickness of the microperforated panel is less than or equal to 1mm, the aperture of the through holes is less than or equal to 1mm, and the perforation rate is 4% -6%.

7. The composite sound absorption device for the drying air duct of the washing machine as claimed in claim 6, wherein the cavity is a rectangular protrusion structure arranged on the upper side wall surface of the drying air duct, wherein the long side of the rectangular protrusion structure is consistent with the direction of the air supply air duct, and the protrusion height is 3cm-4 cm.

8. A composite sound absorption method for a drying air duct of a washing machine, which is characterized in that the method uses the composite sound absorption device of any one of the claims 1 to 7 for sound attenuation.

9. The composite sound absorption method for drying duct of washing machine according to claim 8,

arranging the composite sound absorption device on the side wall of the air duct;

detecting the sound at the upstream of the air duct by using a first sound sensor, converting the sound into a first electric signal and sending the first electric signal to a controller;

detecting sound absorbed by the first passive sound absorption structure by using a second sound sensor, converting the sound into a second point signal and sending the second point signal to the controller;

the controller controls the active sound absorption structure to generate a secondary sound field for balancing noise according to the first electric signal so as to perform active sound absorption, and adjusts the secondary sound field generated by the active sound absorption structure according to the second electric signal.

10. A washing machine comprising a fan, a drying drum and a drying air duct, wherein the fan and the drying drum are connected by the drying air duct, characterized in that the drying air duct employs the composite sound absorption device of any one of claims 1 to 7.

Technical Field

The invention relates to a noise reduction technology of an air duct of a washing machine, in particular to a composite sound absorption device and a composite sound absorption method of a drying air duct of the washing machine and the washing machine.

Background

With the continuous development of washing machine technology, the current washing machine has more and more functions. The problems of noise, vibration and the like also come with the convenience of users. For example, when the washing machine enters a drying stage after completing a dehydration process, the drum is in a low rotation speed state, and noise generated by the drying system is a main noise source of the whole machine.

At present, the most main way to reduce the noise of the air duct is to adopt an impedance composite type noise elimination structure, which is formed by combining an anti-type structure such as an expansion chamber and a resonant cavity with a porous sound absorption material, and can realize the noise control in a wider frequency band. However, due to the inherent defects of the passive control technology, the low-frequency control performance of the passive control technology has obvious limitations, which are mainly reflected in the aspects of narrow control frequency band, unadjustable control frequency, large volume and weight and the like.

In recent years, researchers have gradually studied active noise reduction technologies, and the active noise reduction technologies are widely applied to ventilation ducts of vehicles, aerospace and the like, and can better realize low-frequency-band sound absorption. If the traditional sound absorption structure is combined with the active noise reduction technology, the noise control of the whole frequency band can be realized, and the noise reduction device has great significance on the noise reduction measures of the drying air duct of the washing machine.

Disclosure of Invention

In view of the above, the present invention provides a composite sound absorption device and a composite sound absorption method for a drying air duct of a washing machine, and the washing machine, to solve the above problems, specifically:

the invention provides a composite sound absorption device for a drying air duct of a washing machine, which comprises: at least one group of active sound absorption structure and passive sound absorption structure which are correspondingly arranged,

the passive sound absorption structure is used for passively absorbing noise in the drying air duct and comprises a cavity formed by protruding outwards on the side wall of the drying air duct and a micro-perforated plate covering the opening of the cavity;

the active sound absorption structure is used for actively silencing the noise absorbed by the passive sound absorption structure and comprises a controller, a loudspeaker, a first sound sensor and a second sound sensor,

the loudspeaker is arranged at the top of the cavity, the first sound sensor is arranged in front of the cavity, the second sound sensor is arranged on the side wall of the cavity, and the controller controls the loudspeaker to generate secondary sound field balance passing through the sound pressure of the noise behind the micro-perforated plate according to a first electric signal measured by the first sound sensor and a second electric signal measured by the second sound sensor.

Preferably, the second acoustic sensor is disposed at the center of the cavity side wall.

Preferably, the composite sound absorption device comprises N groups of correspondingly arranged active sound absorption structures and passive sound absorption structures which are sequentially connected,

in the N active sound absorption structures, except that the first sound sensor and the second sound sensor are arranged in the first group of active sound absorption structures, the active sound absorption structures in other groups are only provided with the second sound sensor, and N is a positive integer larger than 1.

Preferably, the N sets of correspondingly arranged active sound absorption structures and passive sound absorption structures are arranged along the wind channel direction.

Preferably, the controller modifies the corresponding speaker according to the second sound sensor in the nth active sound absorbing structure, where N e N.

Preferably, the micro-perforated plate is provided with a plurality of through holes, wherein the thickness of the micro-perforated plate is less than or equal to 1mm, the aperture of each through hole is less than or equal to 1mm, and the perforation rate is 4-6%.

Preferably, the cavity is a rectangular protruding structure arranged on the upper side wall surface of the drying air duct, the long edge of the rectangular protruding structure is consistent with the trend of the air supply air duct, and the protruding height is 3cm-4 cm.

The invention provides a composite sound absorption method for a drying air duct of a washing machine, which uses the composite sound absorption device to perform sound attenuation.

Preferably, the first and second electrodes are formed of a metal,

arranging the composite sound absorption device on the side wall of the air duct;

detecting the sound at the upstream of the air duct by using a first sound sensor, converting the sound into a first electric signal and sending the first electric signal to a controller;

detecting sound absorbed by the first passive sound absorption structure by using a second sound sensor, converting the sound into a second point signal and sending the second point signal to the controller;

the controller controls the active sound absorption structure to generate a secondary sound field for balancing noise according to the first electric signal so as to perform active sound absorption, and adjusts the active sound absorption structure according to the second electric signal.

The invention provides a washing machine, which comprises a fan, a drying cylinder and a drying air duct, wherein the fan and the drying cylinder are connected through the drying air duct, and the drying air duct adopts the composite sound absorption device.

Has the advantages that: according to the invention, the active and passive composite sound absorption structure is arranged in the air duct, so that the noise reduction of a low frequency band and a medium and high frequency band can be realized simultaneously, and the problems of airflow pulsation noise and high motor noise in the pipeline are effectively solved.

Drawings

The above and other objects, features and advantages of the present disclosure will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings. The drawings described below are merely some embodiments of the present disclosure, and other drawings may be derived from those drawings by those of ordinary skill in the art without inventive effort.

FIG. 1 is a schematic view of an active and passive composite sound absorption installation according to an embodiment of the present invention;

FIG. 2 is a schematic cross-sectional view of an active and passive composite sound absorbing structure according to an embodiment of the present invention;

fig. 3 is a schematic diagram illustrating the principle of active and passive composite noise reduction according to an embodiment of the present invention.

In the figure: 1-a first loudspeaker; 2-a second speaker; 3-a first sound sensor; 4-a microperforated plate; 5-a second sound sensor; 6-second sound transducer.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, and "a" and "an" generally include at least two, but do not exclude at least one, unless the context clearly dictates otherwise.

It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

It is also noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a good or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such good or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a commodity or system that includes the element.

In the drying process of the washing machine, the noise of a fan motor and the air flow pulsation noise of an air duct are main noise sources of the whole machine, the technical scheme of the invention starts the structural optimization of the drying air duct, combines the traditional sound absorption structure with the active noise reduction technology and applies the traditional sound absorption structure and the active noise reduction technology to the noise reduction of the air duct, and reduces the noise of the motor and the air flow from a transmission path, thereby improving the sound insulation and noise reduction level of the whole machine.

The active and passive composite sound absorption device for the drying air duct is designed near an air outlet of the air duct and comprises a passive sound absorption structure and an active sound absorption system.

The passive sound absorption structure is a cavity structure and is matched with a novel sound absorption material, namely a micropunch plate, and the passive sound absorption structure has the characteristics of high temperature resistance, high-speed airflow impact resistance and environmental protection, can realize different resonance frequencies by changing the parameters (aperture, plate thickness and perforation rate) of the micropunch plate according to requirements, can be suitable for high-frequency noise reduction in an air duct, and is mainly high-frequency.

The active noise reduction in the composite sound absorption device adopts indirect sound waves with opposite phases and same amplitude to noise signals to offset noise. The active sound absorption system comprises a sound sensor (such as a microphone sensor) and a loudspeaker, wherein the loudspeaker sends sound waves to change back sound pressure of the micro-perforated plate, the microphone is used for detecting whether the sound pressure is zero, the purpose is to change flow resistance, eliminate noise behind the micro-perforated plate, improve middle and low frequency sound absorption performance (mainly low frequency), and realize active and passive composite sound absorption. The invention has small change to the air duct structure, and has small influence on other performances such as air output, drying efficiency and the like while realizing noise reduction.

To further illustrate the technical solution of the present invention, the present invention provides the following examples.