Refrigerator and noise reduction method thereof

Abstract

The invention discloses a refrigerator and a noise reduction method thereof.The refrigerator comprises a refrigerator body, a refrigerating system, a sound pressure sensor, a loudspeaker and a controller, and the refrigerating system is arranged in the refrigerator body and comprises a compressor, a condenser, an evaporator and a fan; the sound pressure sensor is arranged at a preset position outside the box body and is used for detecting sound pressure at the preset position; the loudspeaker is arranged on the box body and is used for playing masking sound to reduce noise; the controller is configured to acquire sound pressure data, detected by the sound pressure sensor, at a preset position during the automatic door opening and closing operation period of the refrigerator; and analyzing the sound pressure data, generating a target masking sound according to a frequency band where a sound pressure maximum value is located, and controlling the loudspeaker to play the target masking sound. The environment sound pressure data is considered based on the sound masking technology, the masking sound is generated according to the frequency band where the maximum value of the environment sound pressure is located for sound masking, and therefore noise generated when the door of the refrigerator is automatically opened and closed is reduced, and user experience is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigerators, and in particular to a refrigerator and a noise reduction method thereof. Background Art

[0002] As people's living standards continue to improve, smart home has become an inevitable development trend. As an indispensable tool for modern home life, refrigerators have become an important part of smart home. Users have higher and higher requirements for the intelligence and performance of refrigerators. At present, refrigerators with automatic door opening and closing have gradually entered users' homes. However, the motor of the automatic door opening and closing refrigerator has a large noise. This noise is easily perceived by users due to its sharp characteristics, which seriously affects the user experience. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a refrigerator and a noise reduction method thereof, which considers the ambient sound pressure data based on the sound masking technology, generates a masking sound according to the frequency band where the maximum value of the ambient sound pressure is located for sound masking, thereby reducing the noise when the refrigerator door is automatically opened and closed, and effectively improving the user experience.

[0004] A refrigerator provided in a first embodiment of the present invention includes:

[0005] The box body, which serves as the supporting structure of the refrigerator, has several compartments inside;

[0006] A refrigeration system, which is arranged in the box, includes a compressor, a condenser, an evaporator and a fan;

[0007] The compressor is used to provide power for the refrigeration cycle of the refrigerator, compressing the low-temperature, low-pressure refrigerant into a high-temperature, high-pressure refrigerant gas;

[0008] The condenser is used to condense and dissipate heat of high-temperature, high-pressure refrigerant gas, and cool the high-temperature, high-pressure refrigerant gas into a normal-temperature, high-pressure refrigerant liquid;

[0009] The evaporator is used to evaporate and absorb heat from a normal temperature and high pressure refrigerant liquid, and vaporize the normal temperature and high pressure refrigerant liquid into a low temperature and low pressure gas;

[0010] The fan is used to allow air to enter the evaporator of the refrigerator for heat exchange and to send the heat-released air into the refrigerator compartment;

[0011] A sound pressure sensor is disposed at a preset position outside the box and is used to detect the sound pressure at the preset position;

[0012] A speaker, which is disposed on the box and is used to play a masking sound to reduce noise;

[0013] The controller is configured to, during the automatic opening and closing of the refrigerator door, obtain sound pressure data at a preset position detected by the sound pressure sensor; analyze the sound pressure data, generate a target masking sound according to the frequency band where the maximum sound pressure value is located, and control the speaker to play the target masking sound.

[0014] In the refrigerator provided by the second embodiment of the present invention, the analyzing of the sound pressure data and generating the target masking sound according to the frequency band where the maximum sound pressure value is located specifically includes:

[0015] Performing one-third octave band processing on the sound pressure data detected by the sound pressure sensor to obtain an unweighted one-third octave band spectrum diagram;

[0016] Performing A-weighting processing on the unweighted one-third octave band spectrum to obtain an A-weighted one-third octave band spectrum;

[0017] Determine the frequency band range where the maximum sound pressure value of the preset frequency band is located according to the A-weighted one-third octave spectrum diagram;

[0018] The corresponding frequency band range of the basic masking sound is fitted and adjusted according to the frequency band range to obtain the target masking sound.

[0019] In the refrigerator provided in the third embodiment of the present invention, the controller is further configured as follows:

[0020] When the compressor is not running, the basic masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0021] In the refrigerator provided in the fourth embodiment of the present invention, the controller is further configured as follows:

[0022] When the refrigerator is powered on for the first time, the preset masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0023] In the refrigerator provided in the fifth embodiment of the present invention, the controller is further configured as follows:

[0024] When the refrigerator is running stably, the speaker is controlled to self-adjust and play the target masking sound, and the target masking sound is linearly correlated with the remaining door closing time from loud to small.

[0025] A refrigerator noise reduction method is provided in a sixth embodiment of the present invention, and the method is applied to a refrigerator including a cabinet, a refrigeration system, a sound pressure sensor, and a speaker; wherein the sound pressure sensor is disposed at a preset position outside the cabinet, and is used to detect the sound pressure at the preset position; the speaker is disposed on the cabinet, and is used to play a masking sound to reduce noise, and the refrigerator noise reduction method includes:

[0026] During the automatic opening and closing of the refrigerator door, obtaining sound pressure data at a preset position detected by the sound pressure sensor;

[0027] The sound pressure data is analyzed, a target masking sound is generated according to a frequency band where the maximum sound pressure value is located, and the speaker is controlled to play the target masking sound.

[0028] In the refrigerator noise reduction method provided by the seventh embodiment of the present invention, the analyzing the sound pressure data and generating the target masking sound according to the frequency band where the maximum sound pressure value is located specifically includes:

[0029] Performing one-third octave band processing on the sound pressure data detected by the sound pressure sensor to obtain an unweighted one-third octave band spectrum diagram;

[0030] Performing A-weighting processing on the unweighted one-third octave band spectrum to obtain an A-weighted one-third octave band spectrum;

[0031] Determine the frequency band range where the maximum sound pressure value of the preset frequency band is located according to the A-weighted one-third octave spectrum diagram;

[0032] The corresponding frequency band range of the basic masking sound is fitted and adjusted according to the frequency band range to obtain the target masking sound.

[0033] In the refrigerator noise reduction method provided in the eighth embodiment of the present invention, the method further includes:

[0034] When the compressor is not running, the basic masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0035] In the refrigerator noise reduction method provided in the ninth embodiment of the present invention, the method further includes:

[0036] When the refrigerator is powered on for the first time, the preset masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0037] In the refrigerator noise reduction method provided in the tenth embodiment of the present invention, the method further includes:

[0038] When the refrigerator is running stably, the speaker is controlled to self-adjust and play the target masking sound, and the target masking sound is linearly correlated with the remaining door closing time from loud to small.

[0039] Compared with the prior art, the beneficial effects of a refrigerator and a noise reduction method thereof provided by an embodiment of the present invention are: during the operation of automatic door opening and closing of the refrigerator, the sound pressure data at a preset position detected by the sound pressure sensor is obtained; the sound pressure data is analyzed, a target masking sound is generated according to the frequency band where the maximum sound pressure is located, and the speaker is controlled to play the target masking sound. The embodiment of the present invention considers the ambient sound pressure data based on the sound masking technology, generates a masking sound according to the frequency band where the maximum ambient sound pressure is located, and performs sound masking, thereby reducing the noise when the refrigerator automatically opens and closes the door, and effectively improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a structural schematic diagram of a refrigerator provided by an embodiment of the present invention;

[0041] Figure 2 It is a structural schematic diagram of a refrigerator body provided by one embodiment of the present invention;

[0042] Figure 3 It is a structural schematic diagram of a single refrigeration system of a refrigerator provided by an embodiment of the present invention;

[0043] Figure 4 It is a structural schematic diagram of a dual refrigeration system of a refrigerator provided by one embodiment of the present invention;

[0044] Figure 5 This is a noise spectrum diagram of a refrigerator automatically opening its door in different states provided by an embodiment of the present invention;

[0045] Figure 6 This is a noise spectrum diagram of a refrigerator automatically closing its door in different states provided by an embodiment of the present invention;

[0046] Figure 7 is a first working flow diagram of a controller in a refrigerator provided by an embodiment of the present invention;

[0047] Figure 8 It is an A-weighted one-third octave spectrum diagram of the sound pressure of a compressor in a refrigerator provided by one embodiment of the present invention;

[0048] Fig. 9 is a second working flow diagram of a controller in a refrigerator provided by an embodiment of the present invention;

[0049] Fig.10 This is a third working flow diagram of a controller in a refrigerator provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0052] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0053] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0054] See also Figure 1 , Figure 1 : is a schematic diagram of the structure of a refrigerator provided in one embodiment of the present invention. The refrigerator provided in the embodiment of the present invention comprises:

[0055] The box body 10, which serves as the supporting structure of the refrigerator, is provided with a plurality of compartments inside;

[0056] A refrigeration system 20, which is arranged in the box, includes a compressor, a condenser, an evaporator and a fan;

[0057] The compressor is used to provide power for the refrigeration cycle of the refrigerator, compressing the low-temperature, low-pressure refrigerant into a high-temperature, high-pressure refrigerant gas;

[0058] The condenser is used to condense and dissipate heat of high-temperature, high-pressure refrigerant gas, and cool the high-temperature, high-pressure refrigerant gas into a normal-temperature, high-pressure refrigerant liquid;

[0059] The evaporator is used to evaporate and absorb heat from a normal temperature and high pressure refrigerant liquid, and vaporize the normal temperature and high pressure refrigerant liquid into a low temperature and low pressure gas;

[0060] The fan is used to allow air to enter the evaporator of the refrigerator for heat exchange and to send the heat-released air into the refrigerator compartment;

[0061] A sound pressure sensor 30, which is disposed at a preset position outside the box 10 and is used to detect the sound pressure at the preset position;

[0062] A speaker 40, which is disposed on the box 10 and is used to play a masking sound to reduce noise;

[0063] The controller 50 is configured to obtain the sound pressure data at a preset position detected by the sound pressure sensor during the automatic opening and closing of the refrigerator door; analyze the sound pressure data, generate a target masking sound according to the frequency band where the maximum sound pressure value is located, and control the speaker to play the target masking sound.

[0064] Specifically, a refrigerator provided in an embodiment of the present invention includes a housing 10, a refrigeration system 20, a sound pressure sensor 30, a speaker 40 and a controller 50. Figure 2 , Figure 2 It is a structural schematic diagram of a refrigerator body provided by an embodiment of the present invention. The refrigerator in this embodiment has an approximately rectangular shape, and the refrigerator includes a body 10 that defines a storage space. The body 10 serves as a supporting structure of the refrigerator, and is provided with a chamber inside, wherein the chamber includes a component storage cavity for placing components in the refrigerator, such as a compressor, etc., and also includes a storage space for storing food, etc. The storage space can be divided into a plurality of storage rooms (i.e., compartments), and the storage rooms can be configured as a refrigeration room, a freezing room, and a temperature-changing room (also called a fresh-keeping room) according to different uses. One or more door bodies 200 are provided at the opening of each storage room, for example, Figure 2 The upper storage room is a cold storage room, which is provided with a double-opening door body. The door body 200 includes a door body outer shell 210 located outside the box body 10, a door body inner liner 220 located inside the box body 10, an upper end cover 230, a lower end cover 240, and an insulation layer located between the door body outer shell 210, the door body inner liner 220, the upper end cover 230, and the lower end cover 240; usually, the insulation layer is filled with foam material. The door body can be pivotally arranged at the opening of the box body, and can also be opened in a drawer-like manner to achieve drawer-like storage.

[0065] The refrigerator performs refrigeration operation through the refrigeration system, providing cold energy to the compartment so as to maintain the compartment at a constant low temperature. Specifically, the refrigeration system of the refrigerator in this embodiment can be a single refrigeration system or a dual refrigeration system. Figure 3 , Figure 3 The single refrigeration system of a refrigerator provided in one embodiment of the present invention is a schematic diagram of the structure. The single refrigeration system of the refrigerator described in the embodiment of the present invention comprises a compressor 1, a condenser 2, an anti-condensation tube 3, a drying filter 4, a capillary tube 5, an evaporator 6 and a gas-liquid separator 7, and the working structure of the refrigeration system includes a compression process, a condensation process, a throttling process and an evaporation process.

[0066] The compression process is as follows: plug in the power cord of the refrigerator, and when the refrigerator needs to be cooled, the compressor 1 starts to work, and the low-temperature and low-pressure refrigerant is sucked into the compressor, compressed into high-temperature and high-pressure superheated gas in the cylinder of the compressor 1, and then discharged to the condenser 2;

[0067] The condensation process is as follows: the high-temperature, high-pressure refrigerant gas dissipates heat through the condenser 2, the temperature continues to drop, and is gradually cooled to a saturated vapor at room temperature and high pressure, and further cooled to a saturated liquid, the temperature no longer drops. The temperature at this time is called the condensation temperature, and the pressure of the refrigerant remains almost unchanged during the entire condensation process;

[0068] The throttling process is as follows: the condensed refrigerant saturated liquid is filtered through the drying filter 4 to remove moisture and impurities and then flows into the capillary 5, through which the throttling and pressure reduction are carried out, and the refrigerant becomes wet steam at room temperature and low pressure;

[0069] The evaporation process is as follows: the refrigerant begins to absorb heat and vaporize in the evaporator 6, which not only reduces the temperature of the evaporator and its surroundings, but also turns the refrigerant into a low-temperature, low-pressure gas. The refrigerant coming out of the evaporator 6 passes through the gas-liquid separator 7 and returns to the compressor 1 again. The above process is repeated to transfer the heat in the refrigerator to the air outside the box, thereby achieving the purpose of refrigeration.

[0070] The fan allows air to continuously enter the fins of the evaporator 6 for heat exchange, and at the same time sends the air that becomes cold after the evaporator 6 releases heat to the refrigerator room through the air duct, so that the air in the room continuously circulates and flows, achieving the purpose of lowering the temperature.

[0071] See also Figure 4 , Figure 4: is a structural schematic diagram of a dual refrigeration system of a refrigerator provided by an embodiment of the present invention. The dual refrigeration system of the refrigerator described in the embodiment of the present invention includes a compressor 21 for compressing the refrigerant, a first capillary tube 14a and a second capillary tube 14b for decompressing the refrigerant, a refrigeration evaporator 15a and a freezing evaporator 15b as heat absorption mechanisms, a three-way valve 17 for controlling the refrigerant flow path, a one-way valve 18 for preventing the refrigerant from flowing back, a dryer 19 for removing moisture in the refrigeration cycle, and a refrigerant junction 13 for connecting the refrigerant flow path, which are connected by a pipe 20 to circulate the refrigerant to form a refrigeration cycle. In this process, the fans 12a and 12b respectively provided for each storage room are used to speed up the air flow rate, thereby speeding up the speed at which the refrigeration evaporator and the freezing evaporator absorb heat and improving the refrigeration speed of the storage room. Among them, the three-way valve 17 has a first outflow port 17a and a second outflow port 17b. When the three-way valve 17 is controlled to open the first outflow port 17a, the refrigerant flows sequentially through the first capillary tube 14a, the refrigeration evaporator 15a, the gas-liquid separator 16a, and the refrigerant junction 13, and then returns to the compressor 21. After passing through the first capillary tube 14a, the low-pressure and low-temperature refrigerant flows through the refrigeration evaporator 15a, performs heat exchange with the refrigeration evaporator 15a and the air in the refrigeration chamber 110, and refrigerates the refrigeration chamber 110. Similarly, when the three-way valve 17 is controlled to open the second outflow port 17b, the refrigerant flows sequentially through the second capillary tube 14b, the freezing evaporator 15b, the gas-liquid separator 16b, and the refrigerant junction 13, and then returns to the compressor 21. After passing through the second capillary tube 14b, the low-pressure and low-temperature refrigerant flows through the freezing evaporator 15b, performs heat exchange with the freezing evaporator 15b and the air in the freezing chamber 120, and refrigerates the freezing chamber 120.

[0072] In the embodiment of the present invention, the sound pressure sensor 30 is arranged on the sides of the left and right sides of the box 10 to detect the sound pressure on both sides of the box. At the same time, the height is set to between 1.5-1.8 meters (the conventional setting is 1.6 meters, which is the human ear position set according to the average height statistics), mainly considering that this height is the maximum point of the user's auditory sensitivity, and the measured data is more accurate. The sound pressure sensor is used to detect the sound pressure size at the preset positions on both sides of the box, and the sound pressure data can be Fourier transformed to obtain the sound pressure data in the frequency domain. The speaker 40 is arranged on the box to play masking sounds to reduce noise. The operation of the speaker is controlled by the main control board. The position of the speaker can be set on the display of the refrigerator box panel. The speaker provided by the display can be used directly, or a new speaker can be placed in the drawer of the automatic door.

[0073] See also Figure 5 and Figure 6 , Figure 5 is a noise spectrum diagram of a refrigerator automatically opening its door in different states provided by an embodiment of the present invention. Figure 6It is a noise spectrum diagram of the automatic door closing of a refrigerator in different states provided by an embodiment of the present invention. By testing the automatic opening and closing of the door in different states, the embodiment of the present invention finds that the noise of the automatic opening and closing of the door is always in a relatively large state, which is easily perceived by the user. Therefore, noise reduction for the automatic opening and closing of the door is necessary. Sound masking technology: The phenomenon that due to the simultaneous existence of two or more sounds, the auditory domain is shifted, resulting in a decrease in the audibility of any one of the sounds. For example, a pure tone with a frequency of 800Hz can be heard by normal people when the sound pressure level is 0dB (if it is lowered further, normal ears will not be able to hear it), that is, the hearing threshold of a pure tone of 800Hz is 0dB. However, in an environment with 70dB of noise, the sound pressure level of a pure tone of 800Hz must be increased to 75dB to be heard, and the decibel increase in the hearing threshold is 75dB (that is, 75dB-0dB). Please refer to Figure 7 , Figure 7 This is a first working flow diagram of a controller in a refrigerator provided by an embodiment of the present invention. During the automatic door opening and closing operation of the refrigerator, the embodiment of the present invention obtains sound pressure data at a preset position detected by a sound pressure sensor. The sound pressure data is analyzed, a target masking sound is generated according to the frequency band where the maximum sound pressure value is located, and a speaker is controlled to play the target masking sound.

[0074] The embodiment of the present invention identifies the current ambient sound pressure components based on the sound pressure sensor, analyzes the main frequency components, and feeds back to the control board. After sound adjustment, the target masking sound with the best composition is adjusted, and then the target masking sound is played through the speaker to achieve the best masking effect. This design can best meet the usage scenarios in the user's home.

[0075] As one of the optional embodiments, analyzing the sound pressure data and generating a target masking sound according to a frequency band where the maximum sound pressure value is located specifically includes:

[0076] Performing one-third octave band processing on the sound pressure data detected by the sound pressure sensor to obtain an unweighted one-third octave band spectrum diagram;

[0077] Performing A-weighting processing on the unweighted one-third octave band spectrum to obtain an A-weighted one-third octave band spectrum;

[0078] Determine the frequency band range where the maximum sound pressure value of the preset frequency band is located according to the A-weighted one-third octave spectrum diagram;

[0079] The corresponding frequency band range of the basic masking sound is fitted and adjusted according to the frequency band range to obtain the target masking sound.

[0080] Specifically, the embodiment of the present invention performs one-third octave processing on the sound pressure data detected by the sound pressure sensor to facilitate viewing of the data, thereby obtaining an unweighted one-third octave spectrum. Then, the unweighted one-third octave spectrum is A-weighted to obtain an A-weighted one-third octave spectrum. A-weighting is to calculate each frequency based on the perception of the human ear, which is most consistent with human perception. Ordinary data may be high, but human perception is not sensitive. For example, please refer to Figure 8 , Figure 8 It is an A-weighted one-third octave spectrum diagram of the sound pressure of a compressor in a refrigerator provided by one embodiment of the present invention. According to the A-weighted one-third octave spectrum diagram, the frequency band range where the maximum sound pressure of a preset frequency band is located is determined. For example, the frequency band range where the two maximum values ​​are located in each of the four frequency bands of 0-200Hz, 200-1000Hz, 1000-4000Hz and 4000-20000Hz, that is, a total of 8 one-third octave frequency band ranges are detected. According to the frequency band range, the corresponding frequency band range of the basic masking sound is fitted and adjusted to obtain the target masking sound. For example, according to the identified 8 maximum value frequency bands, the corresponding frequency band range of the basic masking sound is fitted and adjusted, the sound is amplified, and a target masking sound adapted to the current environmental sound is fitted so that the masking sound can play the maximum role.

[0081] The embodiment of the present invention considers the ambient sound pressure data based on the sound masking technology, generates a masking sound according to the frequency band where the maximum ambient sound pressure is located for sound masking, thereby reducing the noise when the refrigerator door is automatically opened and closed, and effectively improving the user experience.

[0082] As one of the optional embodiments, the controller is further configured to:

[0083] When the compressor is not running, the basic masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0084] For details, please refer to Fig. 9 , Fig. 9This is a second working flow chart of a controller in a refrigerator provided by an embodiment of the present invention. In the embodiment of the present invention, if the compressor is running, the human ear perceives the superimposed sound of the motor and the compressor, and a masking sound needs to be fitted. If the compressor is not running, the human ear only hears the motor sound, which is fixed, and only the basic masking sound is needed at this time. Identifying whether the compressor is running is equivalent to identifying whether the refrigerator is in operation. If it is not running, the basic masking sound can play a masking effect. If it is running, then according to the two maximum frequency bands within 200Hz, whether it can correspond to the operating speed of the compressor, for example, 50Hz, then 50×60=3000 rpm, corresponding to the main control board data whether the compressor is running at 3000 rpm (of course, the main control board can also directly feedback whether the refrigerator is in operation). The reason for this control is that if the corresponding maximum frequency noise cannot be identified, that is, the frequency at the maximum noise value does not correspond to the frequency of the compressor operation, then it means that there is a larger noise source in the environment where the refrigerator is located besides the refrigerator, so the interference from the refrigerator can be eliminated (the noise of the refrigerator will not cause complaints from users), then only the noise of the automatic opening and closing drawers needs to be specifically masked, so the basic masking sound is enough to play a role.

[0085] It should be noted that if there are other abnormal noises when the door is opened and closed, they will also be detected in the sound pressure sensor for fitting and masking sounds. Therefore, if there are a few rare situations when the door is automatically opened and closed, such as the ice maker, vacuum pump and other large noise sources running at the same time, the influence of these noises can also be detected and masked sounds can be performed.

[0086] As one of the optional embodiments, the controller is further configured to:

[0087] When the refrigerator is powered on for the first time, the preset masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0088] For details, please refer to Fig.10 , Fig.10 This is the third working flow diagram of a controller in a refrigerator provided by an embodiment of the present invention. When the refrigerator of the embodiment of the present invention is running stably or in the defrosting recovery period, the sound pressure data at the preset position detected by the sound pressure sensor is obtained, and the sound pressure data is analyzed. The corresponding frequency band range of the basic masking sound is fitted and adjusted according to the frequency band where the maximum sound pressure is located, the sound is amplified, and a target masking sound adapted to the current ambient sound is fitted, and the speaker is controlled to play the target masking sound, so that the masking sound can play the maximum role. When the refrigerator is powered on for the first time, the preset masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0089] As one of the optional embodiments, the controller is further configured to:

[0090] When the refrigerator is running stably, the speaker is controlled to self-adjust and play the target masking sound, and the target masking sound is linearly correlated with the remaining door closing time from loud to small.

[0091] Specifically, in the embodiment of the present invention, when the refrigerator is in stable operation, the speaker is controlled to self-adjust and play the target masking sound, that is, the target masking sound is linearly related to the remaining door closing time from large to small. It should be noted that the high speed cannot self-adjust the size of the masking sound because the body noise of the refrigerator is already very small at a low speed, and even if the masking sound is small, it will not affect the masking effect. However, when the speed is high, if it is adjusted linearly, the sound at the end is very likely to have no masking effect, so at high speed, it is necessary to always maintain the set optimal masking sound.

[0092] Furthermore, the setting of the masking sound in the embodiment of the present invention can be divided into the following three forms:

[0093] 1. All masking sounds are of standard volume. The sound design is simple, but since some of the sound levels are self-adjusting and some are masking sounds that maintain a certain volume, it may cause confusion among users and lead to complaints.

[0094] 2. They are all masking sounds that gradually decrease in volume. You can play them directly. The program settings are simple, but the design of masking sounds is more difficult.

[0095] 3. Low speed is P3\P5 standard sound volume, and the rest are masking sounds that gradually decrease with the sound. The sound design and program design are moderate.

[0096] The embodiment of the present invention also provides a refrigerator noise reduction method, which is applied to a refrigerator including a box, a refrigeration system, an ambient temperature sensor and a speaker; wherein a plurality of compartments are arranged inside the box; the refrigeration system includes a compressor, a condenser, an evaporator and a fan; the compressor is used to provide power for the refrigeration cycle of the refrigerator, compressing the low-temperature, low-pressure refrigerant into a high-temperature, high-pressure refrigerant gas; the condenser is used to condense and dissipate heat for the high-temperature, high-pressure refrigerant gas, and cool the high-temperature, high-pressure refrigerant gas into a normal-temperature, high-pressure refrigerant liquid; the evaporator is used to evaporate and absorb heat for the normal-temperature, high-pressure refrigerant liquid, and vaporize the normal-temperature, high-pressure refrigerant liquid into a low-temperature, low-pressure gas; the fan is used to allow air to enter the evaporator of the refrigerator for heat exchange and send the heat-released air to the refrigerator compartment; the sound pressure sensor is arranged at a preset position outside the box, and is used to detect the sound pressure at the preset position; the speaker is arranged on the box, and is used to play a masking sound to reduce noise. The refrigerator noise reduction method includes:

[0097] S1, during the automatic opening and closing operation of the refrigerator door, obtaining the sound pressure data at a preset position detected by the sound pressure sensor;

[0098] S2, analyzing the sound pressure data, generating a target masking sound according to a frequency band where the maximum sound pressure value is located, and controlling the speaker to play the target masking sound.

[0099] By testing the automatic door opening and closing in different states, the embodiment of the present invention can find that the noise of the automatic door opening and closing is always in a large state, which is easily perceived by the user. Therefore, noise reduction for the automatic door opening and closing is necessary. Sound masking technology: due to the simultaneous existence of two or more sounds, the hearing range is shifted, so that the audibility of any of the sounds is reduced. For example, when the sound pressure level of a pure tone with a frequency of 800Hz is 0dB, normal people can hear it (if it is lowered further, normal people cannot hear it), that is, the hearing threshold of 800Hz pure tone is 0dB. However, in an environment with 70dB noise, the sound pressure level of 800Hz pure tone must be increased to 75dB to be heard, and the decibel number of the hearing threshold increase is 75dB (i.e. 75dB-0dB). During the operation of the automatic door opening and closing of the refrigerator, the embodiment of the present invention obtains the sound pressure data at the preset position detected by the sound pressure sensor. The sound pressure data is analyzed, and a target masking sound is generated according to the frequency band where the maximum sound pressure is located, and the speaker is controlled to play the target masking sound.

[0100] The embodiment of the present invention identifies the current ambient sound pressure components based on the sound pressure sensor, analyzes the main frequency components, and feeds back to the control board. After sound adjustment, the target masking sound with the best composition is adjusted, and then the target masking sound is played through the speaker to achieve the best masking effect. This design can best meet the usage scenarios in the user's home.

[0101] As one of the optional embodiments, analyzing the sound pressure data and generating a target masking sound according to a frequency band where the maximum sound pressure value is located specifically includes:

[0102] Performing one-third octave band processing on the sound pressure data detected by the sound pressure sensor to obtain an unweighted one-third octave band spectrum diagram;

[0103] Performing A-weighting processing on the unweighted one-third octave band spectrum to obtain an A-weighted one-third octave band spectrum;

[0104] Determine the frequency band range where the maximum sound pressure value of the preset frequency band is located according to the A-weighted one-third octave spectrum diagram;

[0105] The corresponding frequency band range of the basic masking sound is fitted and adjusted according to the frequency band range to obtain the target masking sound.

[0106] Specifically, the embodiment of the present invention performs one-third octave band processing on the sound pressure data detected by the sound pressure sensor to facilitate viewing of the data, thereby obtaining an unweighted one-third octave band spectrum diagram. The unweighted one-third octave band spectrum diagram is then A-weighted to obtain an A-weighted one-third octave band spectrum diagram. A-weighting is to calculate each frequency based on the perception of the human ear, which is most in line with human feelings. Ordinary data may be high, but people are not sensitive. According to the A-weighted one-third octave band spectrum diagram, the frequency band range where the maximum sound pressure of the preset frequency band is located is determined. For example, the frequency band range where the two maximum values ​​are located in each of the four frequency bands of 0-200Hz, 200-1000Hz, 1000-4000Hz and 4000-20000Hz, that is, a total of 8 one-third octave band ranges are detected. According to the frequency band range, the corresponding frequency band range of the basic masking sound is fitted and adjusted to obtain the target masking sound. For example, based on the identified 8 maximum value frequency bands, the corresponding frequency band range of the basic masking sound is fitted and adjusted, the sound is amplified, and a target masking sound adapted to the current environmental sound is fitted so that the masking sound can play the maximum role.

[0107] The embodiment of the present invention considers the ambient sound pressure data based on the sound masking technology, generates a masking sound according to the frequency band where the maximum ambient sound pressure is located for sound masking, thereby reducing the noise when the refrigerator door is automatically opened and closed, and effectively improving the user experience.

[0108] As an optional embodiment, the method further includes:

[0109] When the compressor is not running, the basic masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0110] Specifically, in the embodiment of the present invention, if the compressor is running, the human ear perceives the superimposed sound of the motor and the compressor, and a masking sound needs to be fitted. If the compressor is not running, the human ear only hears the motor sound, which is fixed, and only the basic masking sound is needed. Identifying whether the compressor is running is equivalent to identifying whether the refrigerator is in operation. If it is not running, the basic masking sound can play a masking effect. If it is running, then according to the two maximum frequency bands within 200Hz, whether it can correspond to the operating speed of the compressor, for example, 50Hz, then 50×60=3000 rpm, corresponding to the main control board data whether the compressor is running at 3000 rpm, (of course, the main control board can also directly feedback whether the refrigerator is in operation). The reason for this control is that if the corresponding maximum frequency noise cannot be identified, that is, the frequency at the maximum noise value does not correspond to the frequency of the compressor operation, then it means that there is a larger noise source in the environment where the refrigerator is located besides the refrigerator, so the interference from the refrigerator can be eliminated (the noise of the refrigerator will not cause complaints from users), then only the noise of the automatic opening and closing drawer needs to be specifically masked, so the basic masking sound is enough to play a role.

[0111] It should be noted that if there are other abnormal noises when the door is opened and closed, they will also be detected in the sound pressure sensor for fitting and masking sounds. Therefore, if there are a few rare situations when the door is automatically opened and closed, such as the ice maker, vacuum pump and other large noise sources running at the same time, the influence of these noises can also be detected and masked sounds can be performed.

[0112] As an optional embodiment, the method further includes:

[0113] When the refrigerator is powered on for the first time, the preset masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0114] Specifically, when the refrigerator of the embodiment of the present invention is in stable operation or in the defrosting recovery period, the sound pressure data at the preset position detected by the sound pressure sensor is obtained, and the sound pressure data is analyzed, and the corresponding frequency band range of the basic masking sound is fitted and adjusted according to the frequency band where the maximum sound pressure is located, the sound is increased, and a target masking sound adapted to the current environmental sound is fitted, and the speaker is controlled to play the target masking sound, so that the masking sound can play the maximum role. When the refrigerator is powered on for the first time, the preset masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

[0115] As an optional embodiment, the method further includes:

[0116] When the refrigerator is running stably, the speaker is controlled to self-adjust and play the target masking sound, and the target masking sound is linearly correlated with the remaining door closing time from loud to small.

[0117] Specifically, in the embodiment of the present invention, when the refrigerator is in stable operation, the speaker is controlled to self-adjust and play the target masking sound, that is, the target masking sound is linearly related to the remaining door closing time from large to small. It should be noted that the high speed cannot self-adjust the size of the masking sound because the body noise of the refrigerator is already very small at a low speed, and even if the masking sound is small, it will not affect the masking effect. However, when the speed is high, if it is adjusted linearly, the sound at the end is very likely to have no masking effect, so at high speed, it is necessary to always maintain the set optimal masking sound.

[0118] The embodiment of the present invention provides a refrigerator and a noise reduction method thereof. During the operation of automatic door opening and closing of the refrigerator, the sound pressure data at a preset position detected by the sound pressure sensor is obtained; the sound pressure data is analyzed, a target masking sound is generated according to the frequency band where the maximum sound pressure is located, and the speaker is controlled to play the target masking sound. The embodiment of the present invention considers the ambient sound pressure data based on the sound masking technology, generates a masking sound according to the frequency band where the maximum ambient sound pressure is located, and performs sound masking, thereby reducing the noise when the refrigerator automatically opens and closes the door, and effectively improving the user experience.

[0119] It should be noted that the system embodiment described above is merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, in the drawings of the system embodiment provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines. A person of ordinary skill in the art may understand and implement it without paying any creative effort.

[0120] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A refrigerator, characterized in that: include: The box body, which serves as the supporting structure of the refrigerator, has several compartments inside; A refrigeration system, which is arranged in the box, includes a compressor, a condenser, an evaporator and a fan; The compressor is used to provide power for the refrigeration cycle of the refrigerator, compressing the low-temperature, low-pressure refrigerant into a high-temperature, high-pressure refrigerant gas; The condenser is used to condense and dissipate heat of high-temperature, high-pressure refrigerant gas, and cool the high-temperature, high-pressure refrigerant gas into a normal-temperature, high-pressure refrigerant liquid; The evaporator is used to evaporate and absorb heat from a normal temperature and high pressure refrigerant liquid, and vaporize the normal temperature and high pressure refrigerant liquid into a low temperature and low pressure gas; The fan is used to allow air to enter the evaporator of the refrigerator for heat exchange and to send the heat-released air into the refrigerator compartment; A sound pressure sensor is disposed at a preset position outside the box and is used to detect the sound pressure at the preset position; A speaker, which is disposed on the box and is used to play a masking sound to reduce noise; The controller is configured to obtain the sound pressure data at a preset position detected by the sound pressure sensor during the automatic door opening and closing operation of the refrigerator; The sound pressure data is analyzed, a target masking sound is generated according to a frequency band where the maximum sound pressure value is located, and the speaker is controlled to play the target masking sound.

2. The refrigerator according to claim 1, characterized in that: The analyzing the sound pressure data and generating a target masking sound according to a frequency band where the maximum sound pressure value is located specifically includes: Performing one-third octave band processing on the sound pressure data detected by the sound pressure sensor to obtain an unweighted one-third octave band spectrum diagram; Performing A-weighting processing on the unweighted one-third octave band spectrum to obtain an A-weighted one-third octave band spectrum; Determine the frequency band range where the maximum sound pressure value of the preset frequency band is located according to the A-weighted one-third octave spectrum diagram; The corresponding frequency band range of the basic masking sound is fitted and adjusted according to the frequency band range to obtain the target masking sound.

3. The refrigerator according to claim 2, characterized in that: The controller is also configured to: When the compressor is not running, the basic masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

4. The refrigerator according to claim 3, characterized in that: The controller is also configured to: When the refrigerator is powered on for the first time, the preset masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

5. The refrigerator according to claim 4, characterized in that: The controller is also configured to: When the refrigerator is running stably, the speaker is controlled to self-adjust and play the target masking sound, and the target masking sound is linearly correlated with the remaining door closing time from loud to soft.

6. A refrigerator noise reduction method, characterized in that: The method is applied to a refrigerator including a box, a refrigeration system, a sound pressure sensor and a speaker; wherein the sound pressure sensor is arranged at a preset position outside the box, and is used to detect the sound pressure at the preset position; the speaker is arranged on the box, and is used to play a masking sound to reduce noise. The refrigerator noise reduction method includes: During the automatic opening and closing of the refrigerator door, obtaining sound pressure data at a preset position detected by the sound pressure sensor; The sound pressure data is analyzed, a target masking sound is generated according to a frequency band where the maximum sound pressure value is located, and the speaker is controlled to play the target masking sound.

7. The refrigerator noise reduction method according to claim 6, characterized in that: The analyzing the sound pressure data and generating a target masking sound according to a frequency band where the maximum sound pressure value is located specifically includes: Performing one-third octave band processing on the sound pressure data detected by the sound pressure sensor to obtain an unweighted one-third octave band spectrum diagram; Performing A-weighting processing on the unweighted one-third octave band spectrum to obtain an A-weighted one-third octave band spectrum; Determine the frequency band range where the maximum sound pressure value of the preset frequency band is located according to the A-weighted one-third octave spectrum diagram; The corresponding frequency band range of the basic masking sound is fitted and adjusted according to the frequency band range to obtain the target masking sound.

8. The refrigerator noise reduction method according to claim 7, characterized in that: The method further comprises: When the compressor is not running, the basic masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

9. The refrigerator noise reduction method according to claim 8, characterized in that: The method further comprises: When the refrigerator is powered on for the first time, the preset masking sound is used as the target masking sound, and the speaker is controlled to play the target masking sound.

10. The refrigerator noise reduction method according to claim 9, characterized in that: The method further comprises: When the refrigerator is running stably, the speaker is controlled to self-adjust and play the target masking sound, and the target masking sound is linearly correlated with the remaining door closing time from loud to soft.

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