The Research Of Testing Method For Hydraulic Shock Absorber Sound

As an important component of vehicles, hydraulic shock absorbers have an important impact on ride comfort and flexibility. With the development of produce scale, there exist some questions in the process of produce and application. Main fault models are leaking oil, no absorber function and abnormal sound, and abnormal sound is 50 to 60 percents in the reflection of consumers. At present, the shock absorber sound's mechanism is not very clear because of its complexity. Even to the same shock absorber whether it is normal or abnormal depend on different man. So there is an extremely practical significance to probe into test methods for shock absorber abnormal sound.Vibration and sound will be generated when shock absorber works to and fro because of its hydraulic tube structure that used in most modern vehicles. The performance of vehicle shock absorber is impaired by worse vibration and sound, sometimes the sound can be heard clearly by ears, which is called shock absorber abnormal sound. So the automobile quality and ride comfort is impaired heavy.In this thesis, by means of synthesizing a great number of materials and borrowing ideas from the advanced technique and experience home and abroad, the test method for vehicle hydraulic shock absorber sound is proposed. First the feathers of vehicle hydraulic shock absorber vibration and sound is synthesized detailedly, classified as abnormal sound of friction attack, abnormal sound of resonance, abnormal sound of flow cutting and abnormal sound of gas. Base on these researches, a test equipment for vehicle hydraulic shock absorber sound is developed using technologies of computer measure and data collection and disposal, and including shock absorber test stand, sensors and amplifier, LCD, embedded microcomputer and correlative software. Then based on rig test and road test, the data, vibration acceleration signal and power value, and its results are classified and analyzed. And some effective test methods are proposed, which are amplitude spectrum method based on chosen scale energy of amplitude spectrum, time domain method based on the wave shape of acceleration signal and clearances values method based on the time clash occurred.The test method for shock absorber sound has been applied recently in the factory and been justified to satisfy the basic requirement of testing vibration and sound for shock absorber. It is very useful for more understanding the mechanism of shock absorber abnormal sound and for its control.