Development Of Performance Detector For Auto Air Dryer

Auto air dryer is the key component of automotive air brake system, itsperformance has the direct bearing on the performance and service life of air brakesystem. At this stage, auto air dryer manufacturers in domestic only carry out simpletests manually or semi-automatically, because of the lack of efficient andhigh-precision automatic measurement devices. Foreign equipments are tooexpensive, moreover, not suitable for domestic production manufacturers becausethe test standard is different from that in domestic. Therefore, developing a kind ofdedicated on-line detecting system for auto air dryer, has a positive effects ondomestic production quality control and traffic safety.The main contents of this article include the following several aspects:Firstly, the physical structure and work principle of auto air dryer areresearched, then, on the basis of performance analysis, test items and detectionschemes are worked out according to the industrial standard SAE J2384-1999andthe requirements of manufacturer. By means of designing special fixture andhardware testing platform, automatic and effective detection are realized. Thisdevice can detect the specialty performance of unloading valve, safety pressure andseal ability of auto air dryer.Secondly, according to the detection schemes, research how to realize eachhardware module’s function, including pneumatic module, circuit module, dataacquisition system and mechanical structure module, moreover, hardware testplatform is set up. The performance testing software for this detector is developed,which is based on LabVIEW programming environment. The software is responsiblefor coordinating each hardware module’s work, besides, offering human-computerinteraction interface, through which automatic detection and data management areachieved.Thirdly, a large number of repetitive testing is carried through on the system bystandard sample of auto air dryer. On the basis of test data and correlative technicalmanuals, the evaluation of uncertainty for each test item is carried out. What’s more, evaluation of repeatability and accuracy are operated, which is in accordance withthe guide to dedicated detection equipment evaluation method. From the evaluationresults, we know that the confidence interval of each test item can meet designrequirements under a certain degree of confidence, and the measurement capabilityindex can reach the standard evaluation level for new devices. And the detector canbe applied to operating industrial site. At present, this device has been successfullyused at Zhejiang Rong-Zhong Machinery Co., LTD.