A noise testing method for a compressor adapted to a refrigerator

Abstract

The present invention provides a noise testing method for a compressor adapted to a refrigerator, which relates to the field of compressor testing. By designing a multi-mode testing link including initial power-on, standard steady state, quick freezing, defrosting and the like, the operating conditions of a refrigerator in its entire life cycle, including startup, stable operation, rapid refrigeration, defrosting and the like, as well as noise changes during conversions between different operating conditions, can be simulated, thereby greatly improving the ability to evaluate the noise performance of the refrigerator in actual use scenarios. On the basis of the multi-mode testing, combined with sound source analysis and resonance detection, it is possible to accurately distinguish whether the source of the noise problem is an abnormal sound source or other factors such as resonance. According to different root causes of the problem, measures such as adjusting the test scheme or the operating logic, optimizing the speed parameters and the like are adopted respectively, thereby effectively improving the pertinence and effectiveness of product optimization, and reducing the noise of the refrigerator in actual use.

Description

Technical Field

[0001] The invention relates to the field of compressor testing, and in particular to a noise testing method for a compressor adapted to a refrigerator. Background Art

[0002] The noise and vibration of the compressor are coupled with the refrigerator. The requirements for refrigerator noise are getting higher and higher, and the cost control is getting lower and lower. The cost-effectiveness of simply reducing the vibration and noise of the compressor is getting lower and lower, and the effect is lower than the cost investment. The noise and vibration adaptation of the compressor and the refrigerator, without increasing the cost, the compressor and the refrigerator are perfectly adapted to achieve the best state of noise and vibration. The actual scenarios and working conditions of users using refrigerators vary, such as steady state, quick freezing, opening the door, putting in a large amount of frozen food that needs to be refrigerated, etc. The operating speed logic and working conditions of the compressors in the corresponding scenarios are very different. The test method specified in the national standard can only evaluate steady-state noise, and the changes in refrigerator noise under complex working conditions cannot be effectively evaluated and the market risk assessment cannot be obtained.

[0003] The prior art discloses some noise testing methods for refrigerators before they leave the factory, and accepts the steady-state noise test specified in the national standard to determine whether the refrigerator noise is qualified and whether there is a potential risk of user complaints. A single test method is single and one-sided in assessing the risk of refrigerator noise market complaints. Even if the factory inspection is 100% qualified, the refrigerator noise has a variety of working conditions during actual use and is affected by the environment. The existing test methods conduct compressor and refrigerator test analysis independently of each other without forming a linkage. There is a lack of analysis on the noise coupled by the compressor noise vibration on the refrigerator. The traditional test method cannot fully reflect the noise performance in actual use. Summary of the invention

[0004] The purpose of the present invention is to provide a noise testing method for a compressor-adapted refrigerator in response to the defects of the prior art. By designing a multi-mode test link including initial power-on, standard steady state, quick freezing, defrosting, etc., it can simulate the operating conditions of the refrigerator throughout its life cycle, such as startup, stable operation, rapid cooling, defrosting, and the noise changes during the conversion of different operating conditions, thereby greatly improving the ability to evaluate the noise performance of the refrigerator in actual use scenarios. On the basis of multi-mode testing, combined with sound source analysis and resonance detection, it can accurately distinguish whether the source of the noise problem is abnormal sound source or other factors such as resonance. According to different root causes of the problem, measures such as adjusting the test scheme or operating logic and optimizing the speed parameters are taken respectively, thereby effectively improving the pertinence and effectiveness of product optimization and reducing the noise of the refrigerator in actual use.

[0005] In order to solve the above problems, the following solutions are adopted:

[0006] A noise testing method for a compressor adapted to a refrigerator, comprising:

[0007] Arrange sensors and microphones in the test environment to measure the operating status of the refrigerator and the compressor;

[0008] The refrigerator is tested in multiple modes in sequence, including initial power-on, standard steady state, quick freezing mode, and defrosting mode, to determine whether the refrigerator noise is acceptable.

[0009] If the multi-mode test fails, perform sound source analysis and determine the type of abnormality. If the failure is caused by abnormal sound source, adjust and iterate the compressor test plan and re-perform the multi-mode test; if the failure is not caused by abnormal sound source, adjust the operation logic;

[0010] If the multi-mode test is qualified, a constant speed test is performed to determine whether there is resonance. If there is resonance, the constant speed operating parameters are adjusted or a modal test is performed to adjust the scheme to eliminate the resonance. If there is no resonance, the test is qualified.

[0011] Furthermore, the measuring of the operating state of the refrigerator includes measuring the ambient noise of the refrigerator operation, the vibration of the refrigerator structural parts and the temperature of the refrigerator compartment, and the measuring of the operating state of the compressor includes measuring the vibration information of the compressor.

[0012] Furthermore, in the multi-mode test, when the refrigerator is subjected to a standard steady-state test, a load is added for testing, and after the test is passed, the next mode of testing is performed.

[0013] Furthermore, after determining the resonance speed range of the refrigerator through a frequency sweep test, a constant speed test is performed.

[0014] Furthermore, when a constant speed test is performed and resonance is determined to exist, the speed is adjusted to a non-resonant speed determined by a frequency sweep test.

[0015] Furthermore, if the speed cannot be adjusted, the compressor operation plan is adjusted and iterated to change the mode of the resonant components and avoid the resonant frequency.

[0016] Furthermore, when performing sound source analysis, each sound source component is controlled to operate independently.

[0017] Furthermore, a comparison is made between the measured peak frequency of the refrigerator noise and the operating frequency of the compressor to determine whether the noise is a resonance signal.

[0018] Furthermore, when the refrigerator is powered on for the first time, the compressor is set to start running at a low speed and increase the speed in steps.

[0019] Furthermore, the adjustment operation logic includes compressor speed control, operation mode switching and load adjustment.

[0020] Compared with the prior art, the present invention has the following advantages and positive effects:

[0021] In view of the fact that the noise conditions in actual usage scenarios are difficult to be fully evaluated and it is impossible to accurately predict the noise problems in the user experience, by designing multi-mode test links including initial power-on, standard steady state, quick freezing, defrosting, etc., it is possible to simulate the operating conditions of the refrigerator in the entire life cycle, such as startup, stable operation, rapid cooling, defrosting, etc., as well as the noise changes during the conversion of different working conditions, which greatly improves the ability to evaluate the noise performance of the refrigerator in actual usage scenarios; on the basis of multi-mode testing, combined with sound source analysis and resonance detection, it is possible to accurately distinguish whether the source of the noise problem is abnormal sound source or other factors such as resonance. According to different root causes of the problem, measures such as adjusting the test plan or operating logic, optimizing the speed parameters, etc. are taken respectively, which effectively improves the pertinence and effectiveness of product optimization and reduces the noise of the refrigerator in actual use. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0023] Figure 1 Schematic diagram of the noise testing method for a compressor adapted to a refrigerator in Example 1 of the present invention. DETAILED DESCRIPTION

[0024] Example 1

[0025] In a typical embodiment of the present invention, Figure 1 As shown, a noise testing method for a compressor adapted to a refrigerator is provided.

[0026] At present, a single steady-state test method can only determine the eligibility of a product under specific standard conditions. There is a lack of effective evaluation methods for the risk of user complaints that may be caused under complex actual working conditions, making it difficult to prevent potential market risks in advance during product development and quality control. Based on this, this embodiment provides a noise test method for a compressor-adapted refrigerator, which simulates the operating conditions of the refrigerator during its entire life cycle, such as startup, stable operation, rapid cooling, and defrosting, as well as the noise changes during the conversion of different working conditions, thereby improving the ability to evaluate the noise performance of the refrigerator in actual use scenarios and meeting the needs of refrigerator factory testing.

[0027] like Figure 1 As shown, a noise testing method for a compressor adapted to a refrigerator comprises:

[0028] Arrange sensors and microphones in the test environment to measure the operating status of the refrigerator and the compressor;

[0029] The refrigerator is tested in multiple modes in sequence, including initial power-on, standard steady state, quick freezing mode, and defrosting mode, to determine whether the refrigerator noise is acceptable.

[0030] If the multi-mode test fails, perform sound source analysis and determine the type of abnormality. If the failure is caused by abnormal sound source, adjust and iterate the compressor solution and re-perform the multi-mode test. If the failure is not caused by abnormal sound source, adjust the operation logic.

[0031] If the multi-mode test is qualified, a constant speed test is performed to determine whether there is resonance. If there is resonance, the constant speed operating parameters are adjusted or a modal test is performed to adjust the scheme to eliminate the resonance. If there is no resonance, the test is qualified.

[0032] The sensors and microphones are reasonably arranged in the test environment, and their positions are selected based on the analysis of the key operating parts of the refrigerator and compressor and the noise propagation path. For example, sensors are set around the compressor, near the key structural points and heat dissipation parts of the refrigerator body, and microphones are placed in different positions around the refrigerator to ensure that the refrigerator operating status (such as temperature changes, refrigeration cycle status) and compressor operating status (speed, vibration, etc.) information and the generated noise signals can be collected in an all-round and high-precision manner, providing a rich and accurate data basis for subsequent test analysis.

[0033] In this embodiment, according to the measurement point positions on the rectangular hexahedron measurement surface of the floor-standing appliance placed against the wall in GB / T 8059-2016 "Refrigeration appliances for household and similar purposes", the national standard stipulates that the measurement points are arranged with 6 microphones, 1 meter away from the vertical surface of the refrigerator. In addition to the 6 noise measurement points specified in the national standard, the present invention adds vibration measurement points at the compressor X-axis, compressor Y-axis, compressor Z-axis, refrigerator exhaust pipe, refrigerator intake pipe, refrigerator bottom plate, etc., which are used to monitor the vibration of the compressor and the main structural parts of the refrigerator and analyze the resonance noise. In addition, the refrigerator compartment temperature is monitored at the same time, and the refrigerator refrigeration compartment is measured for sound source analysis.

[0034] Initial power-on test: When the refrigerator is powered on for the first time, the system starts the test program to monitor the noise characteristics of the refrigerator at the moment of startup and the warming stage. Due to factors such as current impact and initial operation of mechanical parts during the startup process, unique noise may be generated. This stage of testing can capture the impact sound of the compressor startup and the initial electromagnetic noise of the motor, providing a basis for evaluating the refrigerator startup performance and potential noise sources. The warming stage can capture the noise of the refrigerator compartment from hot to cold and quickly warm up, and evaluate the noise risk of the compressor and refrigerator under high system pressure.

[0035] Standard steady-state test: After the refrigerator reaches a stable state, the test is carried out according to the national steady-state test standard to obtain the noise baseline value of the refrigerator under normal stable working conditions. This ensures that the product meets the basic noise qualification standards and also provides a reference for subsequent comparison of noise changes under different working conditions.

[0036] Quick-freeze mode test: Simulates the use scenario of users quickly freezing a large number of items, and the refrigerator enters the quick-freeze mode. During this period, the compressor runs at high speed and the refrigeration system is under heavy load. The test can detect additional noise caused by factors such as high-speed and large temperature difference refrigeration cycles, such as the sound of rapid refrigerant flow and high-frequency vibration noise of the compressor, and evaluate the noise performance of the refrigerator under extreme refrigeration requirements.

[0037] Defrosting mode test: When the refrigerator enters the defrosting program, the heating element works and the internal temperature and humidity change significantly. This mode test is used to monitor the noise caused by heating, water evaporation, frost melting, etc. during the defrosting process, such as the sound of heating tube expansion and contraction, water flow, etc., to comprehensively examine the acoustic characteristics of the refrigerator under special working conditions.

[0038] It should be pointed out that if the multi-mode test fails, the collected noise signal is analyzed using signal processing technology. Through spectrum analysis, time-frequency domain transformation and other methods, the frequency components and amplitude change rules of the noise signal are identified to determine whether the abnormal noise originates from the sound source itself, such as the specific frequency noise generated by the mechanical failure inside the compressor, the periodic noise caused by the imbalance of the fan blades, etc.

[0039] In this embodiment, a colormap or FFT is used to determine whether the main peak of the noise is a multiple of the compressor operating speed. If the noise peak frequency is an integer multiple of the compressor operating speed frequency, the noise can be determined to be resonance noise. If the noise peak frequency is not an integer multiple of the compressor operating speed frequency, it can be determined that the noise has no direct correlation with the mechanical vibration or pressure pulsation of the compressor. At this time, it is determined whether it is an integer multiple of the fan operating speed frequency. If it is an integer multiple of the fan operating frequency, it can be determined to be caused by the mechanical resonance of the fan, otherwise it is airflow noise or refrigerant fluid noise. When performing a noise source test, control each sound source component to run separately, such as running the fan alone to test the fan noise, and running the compressor alone to test the compressor noise.

[0040] If it is determined that the failure is caused by abnormal sound source, the multi-mode test plan will be adjusted in a targeted manner according to the analysis results. If a component is found to produce abnormal noise under a specific working condition, the monitoring points of the component under that working condition may be increased, the test time interval may be adjusted, or the data collection frequency may be optimized, and the multi-mode test may be repeated to more accurately locate and solve the problem; if the noise exceeds the standard due to unreasonable operating parameters, the operating logic of the refrigerator or compressor may be adjusted, such as optimizing the refrigeration control algorithm, adjusting the compressor start-stop strategy, etc., to reduce the noise level.

[0041] In this embodiment, the noise testing method for a compressor adapted to a refrigerator involves multiple mode testing sequences, and its design is closely centered around the goals of comprehensively testing the noise performance of the refrigerator, accurately locating the root cause of the problem, and effectively optimizing the product.

[0042] Using a progressive detection logic from basic to complex, the test starts in the "first power-on" mode, which is the initial stage of the refrigerator startup. It can first capture the noise characteristics and potential problems of the equipment startup moment and the warm-up stage, laying the foundation for subsequent tests. Then the "national standard steady-state" test is carried out to assess the basic noise level of the refrigerator according to the standard under stable operating conditions to ensure compliance with basic specifications. The subsequent "steady-state load addition" mode simulates the refrigerator load change scenario during daily use by users, and further detects the noise performance under normal operating fluctuations. This transition from no-load steady state to loaded steady state gradually expands the test depth and gradually checks for noise anomalies that may occur under different operating conditions.

[0043] During quick freezing, the compressor runs at high speed and the temperature changes dramatically. The defrosting process involves the operation of the heating element and changes in the internal environment, which are prone to cause unique noise problems. Placing it in the middle of the test process allows for special inspections of these special and critical working conditions to be carried out in a timely manner after basic and conventional working condition inspections, accurately locating the noise source generated under extreme or special conditions, avoiding problems from being missed, and effectively improving the comprehensiveness and accuracy of the test.

[0044] like Figure 1 As shown in the figure, after the multi-mode test is passed, a fixed speed test is performed to simulate the fixed speed operation state of the refrigerator in actual use. By monitoring the vibration and noise response of the refrigerator at different set speeds, it is determined whether there is a resonance phenomenon. The vibration amplitude and frequency of the cabinet are detected by a vibration sensor, and the resonance speed point is determined by combining noise signal analysis.

[0045] If resonance exists, first try to adjust the fixed speed operating parameters, such as fine-tuning the speed value to avoid the resonant frequency range; if the speed cannot be adjusted due to system limitations, iterate the compressor solution, adjust the compressor mode, and re-evaluate the resonance until the resonance is eliminated to ensure stable and low-noise operation of the refrigerator under all operating conditions.

[0046] After various working condition tests in the early stage, the overall operating status and potential problems of the refrigerator have been revealed. The frequency sweep test determines the resonance speed range through frequency sweep, and the fixed speed test further verifies whether there is a resonance risk in the actual operating speed. If resonance is found, the speed can be adjusted or the solution can be iterated based on the test results.

[0047] In this embodiment, the adopted test method can meet the national standard nominal noise test requirements, and can effectively improve the market risk warning capability of refrigerator noise, comprehensively analyze the coupled noise of compressor noise vibration on the refrigerator under different working conditions, comprehensively evaluate the noise performance under different scheme combinations, and comprehensively test various applications of refrigerators. Through the adaptability analysis of refrigerators and compressors and the optimization of the coordination mode of existing schemes, the coupled noise of compressors and refrigerators can be reduced, and the optimal solution for the coupled noise of compressors and refrigerators can be found without increasing costs.

[0048] Measuring the operating status of the refrigerator includes measuring the ambient noise of the refrigerator, the vibration of the refrigerator structure and the temperature of the refrigerator compartment. Measuring the operating status of the compressor includes measuring the vibration information of the compressor. It helps to distinguish between internal noise and external interference noise, and provides a benchmark for accurately evaluating the noise level of the refrigerator itself. The measurement of the refrigerator compartment temperature is closely related to the operation of the refrigeration system. Abnormal temperature changes may be accompanied by abnormal noise of the refrigeration equipment. For example, refrigerant leakage or poor circulation may cause local temperature fluctuations and abnormal sounds. It can also help determine the performance of the refrigerator under different temperature settings and loads.

[0049] In addition, in the multi-modal test, when the refrigerator is undergoing the standard steady-state test, a load is added for testing, and the next mode test is performed after the test is passed; considering that users will constantly put items in or out of the refrigerator in daily life, causing the refrigerator load to be in dynamic change. By adding load during the test, it is possible to observe the noise changes of the refrigerator under different load conditions, and more accurately evaluate the performance of the refrigerator in actual use, avoiding the situation where the test is passed only under no-load or light-load conditions, but the noise exceeds the standard when the actual load increases, thereby effectively improving the reliability and practicality of the test and ensuring that the refrigerator can meet the noise requirements under various load conditions.

[0050] Sweep frequency testing is a key method for determining the resonant speed range of refrigerators. By gradually changing the compressor speed within a certain frequency range and monitoring the vibration and noise response of the refrigerator, the resonance frequency characteristic curve of the refrigerator can be drawn, and the speed range that may cause resonance can be accurately found. This provides an important reference for subsequent fixed speed tests, allowing fixed speed tests to be targeted and verified near key speed points, avoiding blind testing, improving test efficiency and accuracy, and ensuring that the refrigerator will not generate excessive noise due to resonance within the normal operating speed range.

[0051] When resonance is found in the constant speed test, the first measure is to adjust to the non-resonant speed determined by the sweep frequency test. By changing the compressor speed to avoid the resonant frequency, the noise and vibration problems caused by the resonance can be quickly reduced to ensure the smooth operation of the refrigerator. However, in actual applications, there may be some limiting factors, such as the inability to adjust the speed due to energy consumption, refrigeration effect or control system limitations. At this time, the compressor operation plan is adjusted and iterated to change the mode of the resonant component. By optimizing the structural design, material properties or assembly method of the resonant component, its natural frequency is changed to avoid the resonant frequency range and solve the resonance problem.

[0052] When performing sound source analysis, each sound source component is controlled to run separately to achieve refined troubleshooting. The refrigerator contains multiple noise-generating components, such as compressors, fans, solenoid valves, etc. By running each component separately, the interference of other components can be isolated, and the noise characteristics and potential problems of each component can be identified more accurately. For example, when the overall noise of the refrigerator is abnormal, start the compressor and fan separately, and observe the noise conditions when each is running. If the compressor makes abnormal noise when running alone, the compressor can be focused on for in-depth testing, so as to quickly locate the fault sound source and improve the accuracy and efficiency of fault diagnosis.

[0053] By comparing the measured noise peak frequency with the compressor operating frequency, we can determine whether the noise is a resonance signal. When the noise peak frequency is close to or an integer multiple of the compressor operating frequency, there is a high probability of resonance. Through this frequency comparison analysis, we can quickly determine whether the noise is caused by resonance.

[0054] Setting the compressor to start at a low speed and increase the speed in steps when the refrigerator is powered on for the first time is a protection mechanism and performance optimization strategy. At the moment of startup, the compressor is in a cold state and the friction between the mechanical parts is large. Starting at a low speed can reduce the startup impact and wear, and reduce the initial noise. At the same time, the step-by-step speed increase process can allow the compressor to gradually adapt to the operating state and smoothly transition to the normal operating speed, avoiding vibration and noise problems caused by sudden high-speed startup. It also helps the system monitor the operation of the compressor at different speed stages and promptly discover potential fault hazards.

[0055] In this embodiment, the compressor is set to start running from a low speed, 1200-2000rpm→2000-3000rpm→3000-3500rpm→3500-4000rpm→4000rpm or above, with a step-by-step speed increase, and the speed increase span is less than 1000rpm. If the speed increase span is too large, obvious noise changes will be produced.

[0056] Adjusting the operating logic includes aspects such as compressor speed control, operating mode switching and load adjustment. The compressor speed control can dynamically adjust the operating speed of the compressor according to different operating conditions and noise requirements, while ensuring the refrigeration effect and reducing noise. Operating mode switching can reasonably select different refrigeration modes or operating programs according to actual usage needs and environmental conditions, such as automatically switching to energy-saving and silent mode at night or under low load. Load adjustment optimizes the workload distribution of the refrigeration system according to the amount of items in the refrigerator and the temperature distribution, ensuring that the refrigerator can operate efficiently and with low noise under various load conditions. By comprehensively using these means, the overall performance of the refrigerator can be optimized and noise controlled.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A noise testing method for a compressor adapted to a refrigerator, characterized in that: include: Arrange sensors and microphones in the test environment to measure the operating status of the refrigerator and the compressor; The refrigerator is tested in multiple modes in sequence, including initial power-on, standard steady state, quick freezing mode, and defrosting mode, to determine whether the refrigerator noise is acceptable. If the multi-mode test fails, perform sound source analysis and determine the type of abnormality. If the failure is caused by abnormal sound source, adjust and iterate the compressor test plan and re-perform the multi-mode test; if the failure is not caused by abnormal sound source, adjust the operation logic; If the multi-mode test is qualified, a constant speed test is performed to determine whether there is resonance. If there is resonance, the constant speed operating parameters are adjusted or a modal test is performed to adjust the scheme to eliminate the resonance. If there is no resonance, the test is qualified.

2. The noise testing method for a compressor adapted to a refrigerator according to claim 1, characterized in that: The measuring of the refrigerator operation state includes measuring the ambient noise of the refrigerator operation, the vibration of the refrigerator structural parts and the refrigerator compartment temperature, and the measuring of the compressor operation state includes measuring the vibration information of the compressor.

3. The noise testing method for a compressor adapted to a refrigerator according to claim 1 or 2, characterized in that: In the multi-mode test, when the refrigerator is subjected to a standard steady-state test, a load is added for testing, and after the test is passed, the next mode test is performed.

4. The noise testing method for a compressor adapted to a refrigerator according to claim 1, characterized in that: After determining the refrigerator resonant speed range through the sweep frequency test, a constant speed test is performed.

5. The noise testing method for a compressor adapted to a refrigerator according to claim 4, characterized in that: When performing a constant speed test and determining that resonance exists, adjust to the non-resonant speed determined by the swept frequency test.

6. The noise testing method for a compressor adapted to a refrigerator according to claim 4 or 5, characterized in that: If the speed cannot be adjusted, adjust and iterate the compressor operation plan to change the mode of the resonant components and avoid the resonant frequency.

7. The noise testing method for a compressor adapted to a refrigerator according to claim 1, characterized in that: When performing sound source analysis, each sound source component is controlled to operate independently.

8. The noise testing method for a compressor adapted to a refrigerator according to claim 1 or 7, characterized in that: By comparing the measured peak frequency of the refrigerator noise with the operating frequency of the compressor, it is determined whether the noise is a resonance signal.

9. The noise testing method for a compressor adapted to a refrigerator according to claim 1, characterized in that: When the refrigerator is powered on for the first time, the compressor is set to start running at a low speed and increase the speed in steps.

10. The noise testing method for a compressor adapted to a refrigerator according to claim 1, characterized in that: The adjustment operation logic includes compressor speed control, operation mode switching and load adjustment.

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