阅读说明：本技术 一种乘用车液压悬置振动特性识别方法及系统 (Method and system for identifying vibration characteristics of hydraulic suspension of passenger vehicle ) 是由 邱永进 严辉 康润程 于 2021-06-16 设计创作，主要内容包括：本发明提供一种乘用车液压悬置振动特性识别方法及系统,属于汽车噪声振动技术领域,包括液压悬置依次设置为正常安装状态和断开状态,并分别采集怠速工况下的第一数据和第二数据以判断车内嗡嗡音的传递路径是否为液压悬置；液压悬置分别设置为多个不同配置状态,并分别采集怠速工况下的多个第三数据以判断相应配置状态是否为问题状态,车内嗡嗡音是否由相应的组成部件引起,每个配置状态均改变至少一组成部件。本发明通过将液压悬置的正常安装状态分别与多种测试状态进行比对,分析车内嗡嗡音传递路径,寻找车内嗡嗡音产生源头,试验周期短,分析结果精确,能够有效提高工作效率,缩短整车开发周期。(The invention provides a method and a system for identifying vibration characteristics of a hydraulic suspension of a passenger vehicle, belonging to the technical field of noise vibration of vehicles, wherein the method comprises the steps that the hydraulic suspension is sequentially set to be in a normal installation state and a disconnection state, and first data and second data under an idling condition are respectively collected to judge whether a transmission path of humming sound in the vehicle is the hydraulic suspension; the hydraulic suspension is respectively set to be in a plurality of different configuration states, a plurality of third data under the idle working condition are respectively collected to judge whether the corresponding configuration states are problem states or not, whether the buzz in the vehicle is caused by corresponding component parts or not is judged, and at least one component part is changed in each configuration state. According to the invention, the normal installation state of the hydraulic suspension is respectively compared with various test states, the humming transmission path in the vehicle is analyzed, the source of the humming generation in the vehicle is found, the test period is short, the analysis result is accurate, the working efficiency can be effectively improved, and the development period of the whole vehicle is shortened.)

1. A vibration characteristic identification method for a hydraulic suspension of a passenger vehicle is disclosed, wherein the hydraulic suspension comprises a plurality of component parts; characterized in that the method comprises:

step S1, sequentially setting the hydraulic suspension to be in a normal installation state and a disconnection state, and respectively acquiring first data and second data under an idling working condition;

step S2, comparing the first data with the second data, and judging whether the buzz in the car improves:

if yes, determining that the transmission path of the humming sound in the vehicle is hydraulic suspension, and then turning to step S3;

if not, judging that the transmission path of the humming sound in the vehicle is other devices except the hydraulic suspension;

step S3, the hydraulic mount is set to be in a plurality of different configuration states respectively, and a plurality of third data under the idle working condition are collected respectively, and each configuration state changes at least one component;

step S4, comparing the first data with third data which is not compared, and judging whether the noise in the vehicle is improved:

if yes, the corresponding configuration state is judged to be a problem state, and the interior buzzing sound is caused by the corresponding component;

if not, go to step S4;

the first data, the second data and the third data comprise noise signals of noise in the vehicle, vibration signals of a passive end of the hydraulic suspension and rotating speed signals of the engine.

2. The method for identifying the vibration characteristics of a hydraulic mount for passenger vehicles according to claim 1,

the noise signal comprises a noise frequency and a noise amplitude;

the vibration signal includes a vibration frequency and a vibration amplitude.

3. The method for identifying the vibration characteristics of the hydraulic mount for passenger vehicles according to claim 2, wherein the improvement index of whether the noise in the passenger vehicle is improved includes:

the drop amount of the noise amplitude contained in the noise signal in the frequency range of the humming sound in the vehicle exceeds a first preset threshold value, and the first preset threshold value is 2.0dB (A);

the drop amount of the vibration amplitude contained in the vibration signal in the frequency range of the buzzing sound in the vehicle exceeds a second preset threshold value, and the second preset threshold value is 2.0 dB;

the frequency range of the hum in the vehicle is 675Hz to 950 Hz.

4. The method for identifying the vibration characteristics of a hydraulic mount for passenger vehicles according to claim 1,

the hydraulic suspension is respectively connected with the power assembly and the vehicle body end in a normal installation state;

the hydraulic mount is disconnected from the powertrain and connected to the body end in the disconnected state.

5. The method for identifying hydraulic mount vibration characteristics of passenger vehicles according to claim 1, wherein the plurality of different configuration states include:

an upper liquid test state in which the cup is removed and liquid in the upper liquid chamber is evacuated;

testing the state of the rubber main spring, wherein the rubber main spring is punched in the state;

a decoupling film testing state, wherein the upper liquid chamber, the lower liquid chamber and the decoupling film are all removed;

the upper cover plate of the flow channel tests the state, the upper cover plate of the flow channel is removed under this state;

the runner lower cover plate is in a test state, and the runner lower cover plate is removed in the test state;

and testing the state of the mass block, and additionally arranging the mass block at the periphery of the hydraulic suspension in the state.

6. The method for identifying hydraulic suspension vibration characteristics of a passenger car according to claim 5, wherein in step S4, the third data and the first data in the rubber main spring test state are compared to determine whether the in-car buzz sound is improved:

if yes, the testing state of the rubber main spring is judged to be a problem state, and the interior humming sound is caused by the rubber main spring;

if not, go to step S4.

7. The method for identifying the vibration characteristics of the hydraulic mount of the passenger vehicle as claimed in claim 5, wherein in step S4, the third data and the first data in the decoupling film test state are compared to judge whether the in-vehicle hum sound is improved:

if yes, the test state of the decoupling film is judged to be a problem state, and the in-vehicle hum is caused by the decoupling film;

if not, go to step S4.

8. The method for identifying hydraulic suspension vibration characteristics of passenger cars as claimed in claim 5, wherein in step S4, the third data and the first data under the mass test are compared to determine whether the in-car hum sound is improved:

if yes, judging that the conclusion of the in-vehicle humming sound caused by the rubber main spring and the decoupling film is correct;

if not, go to step S4.

9. A vibration characteristic identification system for a hydraulic suspension of a passenger vehicle, wherein the hydraulic suspension comprises a plurality of components; characterized in that the system comprises:

the noise detection module is used for respectively collecting noise signals in the vehicle under the idling working condition when the hydraulic mount is in a normal mounting state, a disconnection state and a plurality of configuration states;

the vibration detection module is used for respectively acquiring vibration signals of the passive end of the hydraulic suspension under the idling working condition when the hydraulic suspension is in a normal installation state, a disconnection state and a plurality of configuration states;

the rotating speed detection module is used for respectively acquiring rotating speed signals of the engine under an idling working condition when the hydraulic suspension is in a normal installation state, a disconnection state and a plurality of configuration states;

the acquisition system is connected with the noise detection module, the vibration detection module and the rotating speed detection module, and is used for acquiring and outputting the noise signals, the vibration signals and the rotating speed signals acquired by the three detection modules;

and the noise vibration analysis system is connected with the acquisition system and is used for receiving the noise signal, the vibration signal and the rotating speed signal and comparing and judging the first data with the second data and the third data respectively.

10. The method for identifying the vibration characteristics of the hydraulic mount of a passenger vehicle as claimed in claim 9, wherein the noise detection module comprises a microphone disposed at the position of the right main driving ear;

the vibration detection module comprises a triaxial accelerometer arranged at the passive end of the hydraulic suspension;

the rotating speed detection module comprises a rotating speed meter arranged at a CAN interface.

Technical Field

The invention relates to the technical field of automobile noise vibration, in particular to a method and a system for identifying vibration characteristics of a hydraulic suspension of a passenger vehicle.

Background

The power assembly and the road surface are two main excitation sources of the passenger car, the vibration of the power assembly is transmitted to the car body through the suspension system to cause the vibration of the car body, and the road surface displacement excitation is transmitted to the power assembly through the suspension system to cause the vibration of the power assembly. Therefore, the suspension system should have a bidirectional vibration isolation function, so as to isolate the vibration and impact of the road surface to the power assembly and isolate the transmission of the vibration of the power assembly to the vehicle body.

In order to effectively attenuate low-frequency large-amplitude vibration caused by uneven road surface and idling gas pressure fluctuation of an engine, the suspension system needs to have the characteristics of high rigidity and large damping within the range of 5 Hz-20 Hz. In order to effectively reduce the noise in the automobile and improve the operation stability of the automobile, the suspension system needs to have the characteristics of low rigidity and small damping above 20 Hz.

As shown in fig. 1, the conventional hydraulic suspension structure is schematically illustrated, and includes a plurality of components, specifically, the components include a vehicle body end mounting screw hole 1, a housing 2, a runner lower cover plate 3, a runner upper cover plate 4, an upper liquid chamber 5, a leather cup 6, a decoupling film 7, an inertia channel 8, a lower liquid chamber 9, a rubber main spring 10, and a power assembly end mounting screw hole 11. The vehicle body end mounting screw hole 1 is arranged on the shell 2 and used for mounting and connecting a hydraulic suspension and a vehicle body, and the power assembly end mounting screw hole 11 is arranged on the rubber main spring 10 and used for mounting and connecting the hydraulic suspension and the power assembly end. The hydraulic suspension is connected with a vehicle body end through a vehicle body end mounting screw hole 1 and is connected with a power assembly through a power assembly end mounting screw hole 11 in a normal mounting state. The hydraulic mount is connected to the vehicle body end through a vehicle body end mounting screw hole 1 and disconnected from the powertrain in the disconnected state.

The runner upper cover plate 4 and the leather cup 6 form an upper liquid chamber 5 with an accommodating space, the runner lower cover plate 3 and the shell 2 form a lower liquid chamber 9 with an accommodating space, an inertia channel 8 is arranged on the outer side of the runner lower cover plate 3, and liquid in the upper liquid chamber and the lower liquid chamber can mutually circulate through the inertia channel 8. The center local ranges of the upper cover plate 4 and the lower cover plate 3 are hollow, the hollow parts are just matched with the size of the decoupling film 7, and the decoupling film 7 can move in a small displacement mode in the direction perpendicular to the upper cover plate 4 and the lower cover plate 3. A rubber main spring 10 is arranged below the decoupling film 7, the bottom of the rubber main spring 10 is provided with the power assembly end mounting screw hole 11, and the power assembly end mounting screw hole 11 penetrates through the bottom of the lower liquid chamber 9. The hydraulic mount can be switched between different configuration states by changing the internal components, for example, the hydraulic mount is switched to the runner cover plate test state by removing the runner cover plate 4.

When the vehicle vibrates greatly at low frequency, the vibration of the power assembly is transmitted to the lower liquid chamber 9 through the main rubber spring 10, liquid in the lower liquid chamber 9 is excited by the vibration of the main rubber spring 10, and pressure difference exists between the upper liquid chamber 5 and the lower liquid chamber 9, so that the liquid flows through the inertia channel 8 to generate energy loss when an inlet, a path and an outlet, the purpose of damping the vibration is achieved, and the vibration transmitted to a vehicle body is reduced.

When the automobile body vibrates in a high-frequency low-amplitude mode, resistance flowing through the inertia channel 8 is large, liquid in the inertia channel hardly flows any more, the liquid in the upper liquid chamber 5 and the liquid in the lower liquid chamber 9 are blocked in a flowing mode, the decoupling film 7 deforms under the action of potential energy of the liquid in the lower liquid chamber 9 to absorb vibration energy of a part of the rubber main spring 10, the vibration is slowed down, and therefore vibration transmitted to the automobile body is slowed down.

The hydraulic suspension overcomes the limitation that the traditional power assembly rubber suspension has small damping, has the characteristics of low frequency, large damping and high frequency and low rigidity, can effectively attenuate the vibration transmitted to the automobile body by the automobile power assembly, achieves the effects of vibration attenuation and noise reduction, has the performance directly related to the vibration level of the whole automobile noise, and is widely applied to the automobile power assembly suspension system.

Most of the current research methods are to adjust the structure of the hydraulic suspension of the automobile power assembly from the aspects of simulation, design and manufacture, mainly to analyze the vibration characteristics of the whole structure, and no effective analysis and identification method is available for the vibration characteristics of the internal structural components of the hydraulic suspension and the caused specific vibration noise problems, particularly the idling state internal hum problem caused by the internal structural components of the hydraulic suspension (subjective evaluation that the noise sounds like hum, and the frequency range of the internal hum is 675Hz to 950Hz), and no specific identification method is available.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a vibration characteristic identification method and system for a hydraulic suspension of a passenger vehicle, which are suitable for analyzing the vibration characteristic of a power assembly suspension system. The normal installation state of the hydraulic suspension is compared with various test states respectively, a buzz transmission path in the vehicle is analyzed, a buzz generation source in the vehicle is found, the test period is short, and the analysis result is accurate.

In order to achieve the above purposes, the technical scheme is as follows:

a vibration characteristic identification method for a hydraulic suspension of a passenger vehicle is disclosed, wherein the hydraulic suspension comprises a plurality of component parts; the method comprises the following steps:

step S1, sequentially setting the hydraulic suspension to be in a normal installation state and a disconnection state, and respectively acquiring first data and second data under an idling working condition;

step S2, comparing the first data with the second data, and judging whether the buzz in the car improves:

if yes, determining that the transmission path of the humming sound in the vehicle is hydraulic suspension, and then turning to step S3;

if not, judging that the transmission path of the humming sound in the vehicle is other devices except the hydraulic suspension;

step S3, the hydraulic mount is set to be in a plurality of different configuration states respectively, and a plurality of third data under the idle working condition are collected respectively, and each configuration state changes at least one component;

step S4, comparing the first data with third data which is not compared, and judging whether the noise in the vehicle is improved:

if yes, the corresponding configuration state is judged to be a problem state, and the interior buzzing sound is caused by the corresponding component;

if not, go to step S4;

the first data, the second data and the third data comprise noise signals of noise in the vehicle, vibration signals of a passive end of the hydraulic suspension and rotating speed signals of the engine.

Preferably, the noise signal comprises a noise frequency and a noise amplitude;

the vibration signal includes a vibration frequency and a vibration amplitude.

Preferably, the improvement index of whether or not the in-vehicle noise improves includes:

the drop amount of the noise amplitude contained in the noise signal in the frequency range of the humming sound in the vehicle exceeds a first preset threshold value, and the first preset threshold value is 2.0dB (A);

the drop amount of the vibration amplitude contained in the vibration signal in the frequency range of the buzzing sound in the vehicle exceeds a second preset threshold value, and the second preset threshold value is 2.0 dB;

the frequency range of the hum in the vehicle is 675Hz to 950 Hz.

Preferably, the hydraulic mount is respectively connected with the power assembly and the vehicle body end in a normal mounting state;

the hydraulic mount is disconnected from the powertrain and connected to the body end in the disconnected state.

Preferably, the plurality of different configuration states include:

an upper liquid test state in which the cup is removed and liquid in the upper liquid chamber is evacuated;

testing the state of the rubber main spring, wherein the rubber main spring is punched in the state;

a decoupling film testing state, wherein the upper liquid chamber, the lower liquid chamber and the decoupling film are all removed;

the upper cover plate of the flow channel tests the state, the upper cover plate of the flow channel is removed under this state;

the runner lower cover plate is in a test state, and the runner lower cover plate is removed in the test state;

and testing the state of the mass block, and additionally arranging the mass block at the periphery of the hydraulic suspension in the state.

Preferably, in step S4, the third data and the first data in the rubber main spring test state are compared to determine whether or not the in-vehicle buzz improves:

if yes, the testing state of the rubber main spring is judged to be a problem state, and the interior humming sound is caused by the rubber main spring;

if not, go to step S4.

Preferably, in step S4, the third data and the first data in the decoupling film test state are compared to determine whether or not the in-vehicle buzz improves:

if yes, the test state of the decoupling film is judged to be a problem state, and the in-vehicle hum is caused by the decoupling film;

if not, go to step S4.

Preferably, in step S4, the third data in the mass test state is compared with the first data to determine whether or not the in-vehicle hum is improved:

if yes, judging that the conclusion of the in-vehicle humming sound caused by the rubber main spring and the decoupling film is correct;

if not, go to step S4.

A vibration characteristic identification system for a hydraulic suspension of a passenger vehicle, wherein the hydraulic suspension comprises a plurality of components; the system comprises:

the noise detection module is used for respectively collecting noise signals in the vehicle under the idling working condition when the hydraulic mount is in a normal mounting state, a disconnection state and a plurality of configuration states;

the vibration detection module is used for respectively acquiring vibration signals of the passive end of the hydraulic suspension under the idling working condition when the hydraulic suspension is in a normal installation state, a disconnection state and a plurality of configuration states;

the rotating speed detection module is used for respectively acquiring rotating speed signals of the engine under an idling working condition when the hydraulic suspension is in a normal installation state, a disconnection state and a plurality of configuration states;

the acquisition system is connected with the noise detection module, the vibration detection module and the rotating speed detection module, and is used for acquiring and outputting the noise signals, the vibration signals and the rotating speed signals acquired by the three detection modules;

and the noise vibration analysis system is connected with the acquisition system and is used for receiving the noise signal, the vibration signal and the rotating speed signal and comparing and judging the first data with the second data and the third data respectively.

Preferably, the noise detection module comprises a microphone arranged at the position of the main driving right ear;

the vibration detection module comprises a triaxial accelerometer arranged at the passive end of the hydraulic suspension;

the rotating speed detection module comprises a rotating speed meter arranged at a CAN interface.

The invention has the beneficial effects that: the normal installation state of the hydraulic mount is compared with various test states respectively, a buzz transmission path in the vehicle is analyzed, a buzz generation source in the vehicle is found, the test period is short, the analysis result is accurate, the working efficiency can be effectively improved, and the development period of the whole vehicle is shortened.

Drawings

Fig. 1 is a schematic structural diagram of a conventional hydraulic mount.

Fig. 2 is a flowchart of a vibration characteristic identification method of a hydraulic mount of a passenger vehicle in an embodiment of the invention.

Fig. 3 is a schematic functional block diagram of a hydraulic mount vibration characteristic identification system of a passenger car in an embodiment of the present invention.

FIG. 4 is a frequency spectrum comparison graph of noise signals under idle conditions when the hydraulic mount is in a normal mounting state and a disconnection state in the embodiment of the invention.

Fig. 5-7 are graphs comparing frequency spectrums of vibration signals under idle speed conditions when the hydraulic mount is in a normal mounting state and a disconnection state according to the embodiment of the invention.

Fig. 8 is a frequency spectrum comparison diagram of a noise signal under an idle working condition when the hydraulic mount is in a normal mounting state, a rubber main spring testing state, and a decoupling film testing state in the embodiment of the invention. Fig. 9 to 11 are frequency spectrum comparison graphs of vibration signals under an idle working condition when the hydraulic mount is in a normal mounting state, a rubber main spring testing state and a decoupling film testing state in the embodiment of the invention.

FIG. 12 is a graph showing a comparison of frequency spectra of noise signals under idle conditions when the hydraulic mount is in a normal installation state and in an upper liquid test state, according to an embodiment of the present invention.

Fig. 13-15 are graphs comparing frequency spectra of vibration signals in idle operation with hydraulic mount in normal installation and upper fluid test, according to an embodiment of the present invention.

Fig. 16 is a frequency spectrum comparison diagram of noise signals under an idle condition when the hydraulic mount is in a runner upper cover plate test state, a runner lower cover plate test state, and a mass block test state in the embodiment of the invention.

Fig. 17-19 are frequency spectrum comparison graphs of vibration signals under idle conditions when the hydraulic mount is in the runner upper cover plate test state, the runner lower cover plate test state, and the mass block test state in the embodiment of the invention.

FIG. 20 is a frequency spectrum comparison graph of noise signals under idle conditions when the hydraulic mount is in a normal mounting state and a mass testing state according to the embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific examples described herein are intended to be illustrative only and are not intended to be limiting. Moreover, all other embodiments that can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort belong to the protection scope of the present invention.

The present invention will be described in further detail with reference to the accompanying drawings and examples.

As shown in fig. 2, the invention discloses a method for identifying vibration characteristics of a hydraulic suspension of a passenger vehicle, which comprises the following steps: the method comprises the steps of collecting first data of the hydraulic suspension in a normal installation state and second data of the hydraulic suspension in a disconnection state, comparing the second data with the first data to judge whether the hydraulic suspension is a main transmission path, if the second data is compared with the first data, the in-vehicle humming sound is obviously improved or disappears, the hydraulic suspension is a main transmission path, and if the second data is compared with the first data, the in-vehicle humming sound is not obviously changed, the hydraulic suspension is not the main transmission path. Furthermore, third data of the hydraulic suspension in different configuration states are collected, and through comparison of the third data with the first data, which component in the hydraulic suspension is a source causing the in-vehicle humming sound is judged. The first data, the second data and the third data comprise noise signals of noise in the vehicle, vibration signals of a passive end of the hydraulic suspension and rotating speed signals of the engine.

Specifically, the method for identifying the vibration characteristics of the hydraulic suspension of the passenger vehicle comprises the following steps:

and step S1, sequentially setting the hydraulic suspension to be in a normal installation state and a disconnection state, and respectively acquiring first data and second data under the idle working condition.

Step S2, comparing the first data with the second data, and judging whether the buzz in the car improves:

if yes, the transmission path of the in-vehicle buzz is determined to be the hydraulic mount, and then the process goes to step S3.

If not, the transmission path of the humming sound in the vehicle is determined to be other devices besides the hydraulic suspension (such as other two rubber suspensions of the power train: a left suspension and a torsion-resistant suspension).

Step S3, the hydraulic mount is set to be in a plurality of different configuration states respectively, and a plurality of third data under the idle working condition are collected respectively, and each configuration state changes at least one component.

Step S4, comparing the first data with third data not compared, and determining whether the in-vehicle buzz improves:

if yes, the corresponding configuration state is judged to be a problem state, and the in-vehicle buzzing sound is caused by the corresponding component.

If not, go to step S4.

In the embodiment, the normal installation state of the hydraulic suspension is compared with various test states (including a disconnection state and a configuration state) respectively, the installation state of the hydraulic suspension of the power assembly and the internal structure of the hydraulic suspension are changed, the vibration of the hydraulic suspension of the power assembly and the noise in the vehicle are subjected to data processing and analysis according to the idling condition, the phenomenon of humming sound in the idling vehicle is rapidly identified (the frequency range of the humming sound in the vehicle is 675 Hz-950 Hz), the transmission path of the humming sound in the vehicle is analyzed, the generation source of the humming sound in the vehicle is found, the later-stage problem analysis is assisted, the problem solving efficiency is improved, the test period is short, the analysis result is accurate, the working efficiency can be effectively improved, and the development cycle of the whole vehicle is shortened.

The identification method has important significance for improving the pertinence of the hydraulic suspension of the automobile power assembly.

In a preferred embodiment, the noise signal includes a noise frequency and a noise amplitude. The vibration signal includes a vibration frequency and a vibration amplitude.

The subjective evaluation criterion of whether the in-vehicle buzz is improved is that the in-vehicle noise (namely buzz) is obviously reduced or disappears, and objective improvement indexes of the subjective evaluation criterion comprise:

the amount of drop in the noise amplitude contained in the noise signal in the frequency range of the in-vehicle hum exceeds a first predetermined threshold value, which is 2.0db (a).

The amount of decrease in the amplitude of the vibrations contained in the vibration signal in the frequency range of the in-vehicle hum exceeds a second preset threshold value, which is 2.0 dB.

Subjective evaluation shows that the interior buzz is improved obviously.

In a preferred embodiment, the plurality of different configuration states include:

upper liquid test condition, in which the lower cup is removed and the liquid in the upper liquid chamber is evacuated.

And (3) testing the state of the main rubber spring, wherein holes are punched at the periphery of the main rubber spring to reduce the rigidity of the main rubber spring.

The decoupling membrane tests the state in which the upper fluid chamber, the lower fluid chamber, and the decoupling membrane are all removed.

The runner upper cover plate tests a state in which the runner upper cover plate is removed.

And the lower runner cover plate tests the state, and the lower runner cover plate is removed in the state.

And testing the state of the mass block, and additionally arranging the mass block at the periphery of the hydraulic suspension in the state.

In a preferred embodiment, in the step S4, the third data and the first data in the upper liquid test state are collected and compared to determine whether or not an in-vehicle buzz is improved, and if the in-vehicle buzz is improved, it is determined that the upper liquid test state is a problem state, the in-vehicle buzz is caused by the liquid in the upper liquid chamber, and if the in-vehicle buzz is not improved, it is determined that the upper liquid test state is a normal state, the in-vehicle buzz is not caused by the liquid in the upper liquid chamber, and then the routine proceeds to a step S4 to determine the third data in the other arrangement state.

In a preferred embodiment, in the step S4, the third data and the first data in the rubber main spring test state are collected and compared to determine whether or not the in-vehicle hum is improved, and if the in-vehicle hum is improved, it is determined that the rubber main spring test state is a problem state, the in-vehicle hum is caused by the rubber main spring and is generally caused by the structural resonance of the rubber main spring, and if the in-vehicle hum is not improved, it is determined that the rubber main spring test state is a normal state, and the in-vehicle hum is not caused by the rubber main spring, and then the process proceeds to the step S4 to determine the third data in the other arrangement state.

In a preferred embodiment, in the step S4, third data and the first data in the decoupling film test state are collected and compared to determine whether an in-vehicle hum is improved, if so, the decoupling film test state is determined to be a problem state, the in-vehicle hum is caused by the decoupling film and generally caused by high-frequency hardening of the inertial decoupling film, if not, the decoupling film test state is determined to be a normal state, the in-vehicle hum is not caused by the decoupling film, and then, the step S4 is performed to continuously determine the third data in other configuration states.

In a preferred embodiment, in the step S4, the third data and the first data in the runner cover test state are compared to determine whether or not an interior buzz has improved, and if the third data and the first data have improved, it is determined that the runner cover test state is a problem state, the interior buzz is caused by the runner cover, and if the third data has not improved, it is determined that the runner cover test state is a normal state, and the interior buzz is not caused by the runner cover, and then the routine goes to step S4 to continue determining the third data in the other arrangement state.

In a preferred embodiment, in the step S4, the third data and the first data in the under-flow-path-cover-test state are compared to determine whether or not an interior hum is improved, and if the improvement is found, the under-flow-path-cover-test state is determined to be a problem state, the interior hum is caused by the under-flow-path cover, and if the improvement is not found, the under-flow-path-cover-test state is determined to be a normal state, and the interior hum is not caused by the under-flow-path cover, and then the routine proceeds to step S4 to determine the third data in the other arrangement state.

In a preferred embodiment, the third data in the rubber main spring test state and the third data in the decoupling film test state are analyzed, and after the idling in-vehicle buzzing sound is generated due to the structural resonance of the rubber main spring and the high-frequency hardening characteristic of the inertial decoupling film. And verifying the conclusion by using the third data of the test state of the mass block, basically eliminating the buzzing sound in the vehicle after the hydraulic suspension is additionally provided with the mass block, and verifying the correctness of the conclusion.

Specifically, in step S4, the third data in the mass test state and the first data are compared to determine whether the in-vehicle hum is improved, and if the in-vehicle hum is improved, it is determined that the conclusion of the in-vehicle hum caused by the rubber main spring and the decoupling film is correct, and if the in-vehicle hum is not improved, the process then proceeds to step S4 to continuously determine the third data in the other configuration states.

As shown in fig. 3, the invention also discloses a vibration characteristic identification system for a hydraulic mount of a passenger vehicle, which comprises:

the noise detection module 13 comprises a microphone arranged at the position of the right ear of the driver, and is used for respectively collecting noise signals in the vehicle under the idling condition when the hydraulic mount is in a normal mounting state, a disconnection state and a plurality of configuration states.

And the vibration detection module 14 comprises a triaxial accelerometer arranged at the passive end of the hydraulic suspension, and is used for respectively acquiring vibration signals of the passive end of the hydraulic suspension under the idle working condition when the hydraulic suspension is in a normal installation state, a disconnection state and a plurality of configuration states.

The rotating speed detection module 12 comprises a tachometer arranged at a CAN interface and is used for respectively collecting rotating speed signals of the engine crankshaft under the idle working condition when the hydraulic suspension is in a normal installation state, a disconnection state and a plurality of configuration states.

And the acquisition system 15 is connected with the noise detection module 13, the vibration detection module 14 and the rotating speed detection module 12, and is used for acquiring the noise signals, the vibration signals and the rotating speed signals acquired by the three detection modules, classifying and integrating various signals and outputting the signals.

And the noise vibration analysis system 16 is connected with the acquisition system 15 and is used for receiving the noise signal, the vibration signal and the rotating speed signal and comparing and judging the first data with the second data and the third data respectively. The noise vibration analysis system 16 processes the rotation speed signal, the vibration signal and the noise signal collected by the collection system 15 into a two-dimensional graph in a time domain and a frequency domain, so that the vibration characteristic of the hydraulic mount can be conveniently analyzed.

And the filtering playback system 17 is used for filtering and playing back the noise in the vehicle, performing frequency filtering and time interception on the collected noise signals through a frequency domain filter and a time domain data clipping function in software, separating out the frequency range in which the buzzing sound in the vehicle appears, and obtaining the frequency range of the buzzing sound in the idling vehicle from 675Hz to 950 Hz.

Semi-anechoic chamber and control software for subjective evaluation.

In a specific embodiment, a professional semi-anechoic chamber is selected for a vehicle with a problem in the early stage of testing, the vehicle is subjectively evaluated in idle working conditions, five groups of professionals are used for evaluating independently, the frequency of humming sounds in the vehicle is high, the vibration of the whole vehicle with consistent characteristics is judged, the possibility that the humming sounds are excited by an engine and transmitted into the vehicle through hydraulic suspension is high unlike air noise, and the influence on the comfort of drivers and passengers is very large. Therefore, the subjective evaluation indicates the direction for next test point arrangement and problem analysis, and the problem solving efficiency is improved.

The main idea of the test phase is that a source-path-response idea can be identified through three aspects of an excitation source, a noise transmission path and noise response.

The excitation source, namely the power assembly, has small excitation contribution to the middle and high frequency under the idle working condition, and the test with the noise transmission path as a variable is the most effective diagnosis method. The noise transmission path includes the hydraulic mount, the intake system, the exhaust system, and the air inside each system, and the possibility of noise generation due to the structure transmission path is the greatest because the presence of structure resonance in the vehicle is subjectively evaluated for medium-high frequency noise in view of its frequency range of 675Hz to 950Hz, because the frequency of the medium-high frequency noise is the middle-high frequency noise.

The in-vehicle response point, namely the position of the right ear of the driver is the most obvious in-vehicle hum, and the interference of the position of the right ear relative to the position of the left ear is the least, so that the in-vehicle hum is more obvious and is convenient to recognize and analyze.

By controlling the structural state of a larger suspicious transmission path, namely different configuration states, the complex transmission path analysis is avoided, and an efficient and definite diagnosis and identification method is provided.

The analysis tool comprises a subjective evaluation module 13, a vibration detection module 14, a rotating speed detection module 12, a noise vibration analysis system 16, a filtering playback system 17 and the like, wherein the noise detection module 13 comprises a microphone arranged at the position of a main driving right ear, the vibration detection module 14 comprises a triaxial accelerometer arranged at a hydraulic suspension passive end, and the rotating speed detection module 12 comprises a tachometer arranged at a CAN interface.

The test working condition is the idling working condition of the whole vehicle. The test site is a semi-anechoic chamber and ensures that the ambient noise is at least 10dB lower than the tested noise, and other interference factors are very small. According to the main idea, the specific position and the occurrence mechanism of the buzz problem in the vehicle are finally diagnosed and identified by controlling the transmission path in the main idea and by means of an analysis tool, and the accuracy of problem analysis is verified by the mass block. And (5) verifying whether the humming sound in the vehicle is basically eliminated after verifying and verifying the hydraulic suspension added with the mass block, and if the humming sound disappears, judging that the noise source is correct.

Specifically, as shown in fig. 4, it is a frequency spectrum comparison diagram of noise signals under idle operating conditions when the hydraulic mount is in a normal mounting state and a disconnection state, wherein first, second, the hydraulic mount is in the normal mounting state and the disconnection state respectively. The noise amplitude in the vehicle in the off state is reduced by 6.7dB (A) in the frequency range of 675Hz to 950Hz, and the peak value of the frequency spectrum disappears.

As shown in fig. 5 to 7, the graphs are frequency spectrum comparison graphs of vibration signals under the idle working condition when the hydraulic mount is in the normal mounting state and the disconnection state in sequence, wherein the third, fifth and seventh represent the X-direction frequency spectrum, the Y-direction frequency spectrum and the Z-direction frequency spectrum of the passive end of the hydraulic mount under the idle working condition when the hydraulic mount is in the normal mounting state, and the fourth, sixth and eighth represent the X-direction frequency spectrum, the Y-direction frequency spectrum and the Z-direction frequency spectrum of the passive end of the hydraulic mount under the idle working condition when the hydraulic mount is in the disconnection state. The vibration amplitudes of the hydraulic suspension passive end in the X direction, the Y direction and the Z direction in the disconnection state are sequentially reduced by 35.0dB, 28.4dB and 32.6dB in the frequency range of 675 Hz-950 Hz, and the peak value of the frequency spectrum disappears.

As can be seen from fig. 4 to 7, the in-vehicle sound is improved, the hydraulic mount is the main transmission path of the in-vehicle sound, and it is necessary to further analyze which component parts in the hydraulic mount are the source of the problem causing the in-vehicle sound.

As shown in fig. 8, the diagram is a frequency spectrum comparison diagram of noise signals under an idle working condition when the hydraulic mount is in a normal mounting state, a rubber main spring testing state, and a decoupling film testing state, wherein (r), (nini), and (r) respectively represent the normal mounting state of the hydraulic mount, the rubber main spring testing state, and the decoupling film testing state. The noise amplitude in the vehicle in the test state of the rubber main spring is reduced by 4.6dB (A) within the frequency range of 675Hz to 950 Hz. The noise amplitude in the decoupling film in a test state is reduced by 4.7dB (A) within the frequency range of 675Hz to 950 Hz.

As shown in fig. 9 to 11, which are frequency spectrum comparison diagrams of vibration signals under idle working conditions when the hydraulic mount is in a normal mounting state, a rubber main spring test state, and a decoupling film test state, wherein the third, fifth, and seventh represent the X-direction frequency spectrum, the Y-direction frequency spectrum, and the Z-direction frequency spectrum of the passive end of the hydraulic mount under idle working conditions when the hydraulic mount is in the normal mounting state, respectively shows the X-direction frequency spectrum, the Y-direction frequency spectrum and the Z-direction frequency spectrum of the passive end of the hydraulic suspension under the idle working condition when the hydraulic suspension is in a rubber main spring testing state,the method is characterized in that the method respectively shows the X-direction frequency spectrum, the Y-direction frequency spectrum and the Z-direction frequency spectrum of the passive end of the hydraulic suspension under the idle working condition when the hydraulic suspension is in a decoupling film test state. The vibration amplitudes of the hydraulic suspension passive end in the X direction, the Y direction and the Z direction of the rubber main spring in the test state are sequentially reduced by 10.4dB, 10.5dB and 10 DEG within the frequency range of 675Hz to 950Hz10.7 dB. The vibration amplitudes of the passive end of the decoupling film in the X direction, the Y direction and the Z direction are sequentially reduced by 10.1dB, 12.1dB and 10.4dB within the frequency range of 675Hz to 950Hz in a test state.

As is apparent from fig. 8 to 11, the in-vehicle noise is improved, and the characteristics of the rubber main spring structure resonance and the inertial decoupling film high-frequency hardening cause the occurrence of the idling in-vehicle noise.

FIG. 12 is a graph showing the comparison of the frequency spectrum of the noise signal under idle conditions when the hydraulic mount is in the normal installation state and the upper liquid test state, wherein,Respectively showing the hydraulic suspension in a normal installation state and an upper liquid test state. The noise amplitude in the upper liquid test state is not obviously reduced within the frequency range of 675Hz to 950 Hz.

As shown in fig. 13 to 15, which are frequency spectrum comparison diagrams of vibration signals under idle working condition when the hydraulic mount is in normal installation state and upper liquid test state, wherein, the third, the fifth and the seventh represent the frequency spectrum of the driven end of the hydraulic mount, the frequency spectrum of the X direction, the frequency spectrum of the Y direction and the frequency spectrum of the Z direction respectively under idle working condition when the hydraulic mount is in normal installation state,respectively showing the X-direction frequency spectrum, the Y-direction frequency spectrum and the Z-direction frequency spectrum of the passive end of the hydraulic suspension under the idle working condition when the hydraulic suspension is in the upper liquid testing state. The vibration amplitudes of the hydraulic suspension passive end in the X direction, the Y direction and the Z direction in the disconnection state are not obviously reduced within the frequency range of 675Hz to 950 Hz.

As can be seen from fig. 12 to 15, the improvement of the in-vehicle buzz is not significant, and the upper liquid chamber liquid is not a source of the problem that the in-vehicle buzz is generated.

Fig. 16 is a graph showing a comparison of frequency spectrums of noise signals under idle conditions when the hydraulic mount is in the runner top cover plate test state, the runner bottom cover plate test state, and the mass block test state, wherein,the test state of the hydraulic suspension on the upper cover plate of the runner, the test state of the lower cover plate of the runner and the test state of the mass block are respectively shown. The in-vehicle noise amplitude is not obviously reduced within the frequency range of 675Hz to 950Hz in the test state of the upper cover plate of the flow channel and the test state of the lower cover plate of the flow channel.

Fig. 17 to 19 are graphs showing frequency spectra of vibration signals under idle conditions when the hydraulic mount is in the runner top cover plate test state, the runner bottom cover plate test state, and the mass block test state, wherein,respectively showing the X-direction frequency spectrum, the Y-direction frequency spectrum and the Z-direction frequency spectrum of the passive end of the hydraulic suspension under the idle working condition when the hydraulic suspension is in the mass block testing state,respectively showing the X-direction frequency spectrum, the Y-direction frequency spectrum and the Z-direction frequency spectrum of the passive end of the hydraulic suspension under the idle working condition when the hydraulic suspension is in the test state of the upper cover plate of the runner,the method respectively shows the X-direction frequency spectrum, the Y-direction frequency spectrum and the Z-direction frequency spectrum of the passive end of the hydraulic suspension under the idling working condition when the hydraulic suspension is in the testing state of the lower cover plate of the runner. The vibration amplitudes of the hydraulic suspension passive ends in the X direction, the Y direction and the Z direction of the runner upper cover plate and the runner lower cover plate in the test state are not obviously reduced within the frequency range of 675Hz to 950 Hz.

As can be seen from fig. 16 to 19, the improvement of the in-vehicle buzz is not significant, and the runner cover upper and the runner cover lower are not a source of the problem of causing the in-vehicle buzz.

FIG. 20 is a graph showing the comparison of the frequency spectrum of the noise signal under the idle condition when the hydraulic mount is in the normal mounting state and the mass testing state, wherein,Respectively shows that the hydraulic suspension is in a normal installation state and qualityBlock test status. The noise amplitude in the mass block test state vehicle is reduced by 7.7dB (A) within the frequency range of 675Hz to 950 Hz.

As can be seen from fig. 20, it is judged that the occurrence of an idling in-vehicle noise is correct due to the characteristics of the rubber main spring structural resonance and the high-frequency hardening of the inertial decoupling film.

In the above fig. 4, 8, 12, 16, and 20, the abscissa represents the frequency (unit: Hz), and the ordinate represents the noise sound pressure level (db (a), unit: pa).

In FIGS. 5 to 7, 9 to 11, 13 to 15, and 17 to 19, the abscissa represents the frequency (unit: Hz), and the ordinate represents the vibration acceleration level (dB, unit: m/s)²)。

The filter playback system 17 provides an auxiliary judgment that the noise variation combined with the vibration variation can judge whether the vibration and noise disappear. The filtering playback system 17 performs noise separation and noise playback on the noise signals acquired under all the states of the hydraulic mount, wherein the noise separation refers to separating the noise at the peak according to the noise frequency spectrum, comparing the noise with the in-vehicle hum acquired under the original state, and judging whether the noise at the peak is the same as the in-vehicle hum.

Aiming at the problems of medium-high frequency noise caused by the resonance of a rubber main spring structure of a hydraulic suspension and the high-frequency hardening of an inertial decoupling film, a mass block can be additionally arranged on a hydraulic suspension of a power assembly to absorb medium-high frequency energy caused by the resonance of the rubber main spring structure of the hydraulic suspension of the power assembly and the high-frequency hardening of the inertial decoupling film, and the influence of the medium-high frequency energy is improved. Under the idle working condition, the noise in the vehicle is reduced by 7.7dB (A) within the range of 675Hz to 950Hz, the subjective evaluation of the buzz in the vehicle disappears, the improvement effect is obvious, and therefore the conclusion that the buzz in the vehicle is generated due to the structural resonance of the hydraulic suspension rubber main spring and the high-frequency hardening of the inertia decoupling film is verified to be correct. According to the method, the change of the state of the transmission path is controlled by means of the subjective evaluation and filtering playback system 17 according to a source-path-response thought, the vibration characteristics of the hydraulic suspension of the powertrain are rapidly identified, the source of the buzz problem in the idling vehicle is found, the test period is short, the target is clear, and the method is the most effective identification method.

The range of humming audio frequencies in the vehicle can be quickly determined by the filtered playback system 17, specifically quantifying the human auditory perception. Professional subjective evaluation can direct the in-vehicle buzz problem diagnosis prior to testing, avoiding inefficient or unworked work from occurring. The test points are few, the data analysis time is shortened, the problem is clear, the correctness of the conclusion is verified by additionally arranging the mass block at the later stage, and meanwhile, the objective improvement and quantitative change of the hum in the vehicle is provided. In a word, improve work efficiency, shorten whole car development cycle.

The present invention is not limited to the above-described embodiments, and it will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and such modifications and improvements are also considered to be within the scope of the present invention. Those not described in detail in this specification are within the skill of the art.