Dynamic Analysis And Experimental Study Of Timing Silent Chain System For Modern Gasoline Engine

Timing salient chain system is wildly used in engine valve train system, accordingto the higher requirement of engine performance. However, the relative researchinstitutes do not have independent research and design capability on timing salientchain development at the domestic, caused the key technology has been monopolizedby foreign. Based on resent research status on timing salient chain system, andsupported by science and technology major planning project of Jilin province “keydevelopment technology on timing salient chain system for modern gasoline engine”,a whole timing salient chain system was developed for a gasoline engine, this paperwas focus on dynamic characteristics analysis of timing chain system andexperimental investigation. Research results provide a significant theoretical referenceand also upgrading independent research and design capability on timing chainsystem.Firstly, four-stroke gasoline engine working mechanism is introduced in this paper,ventilation process is described in detail, and the basic development process of timingsalient chain system is expounded. Secondly, according to the transmissioncharacteristics analysis results of timing chain system, the reason that caused polygoneffect was investigated, and the theory formula about transverse and longitudinalfluctuation during chain meshing process were deduced, using these formulatransverse and longitudinal fluctuation values were calculated when chain platemeshing with three type of sprockets respectively. In order to verify the design of thistiming silent chain drive system can meet the requirement of noise and vibration,CAE analysis were done to investigating the fluctuation values during meshingprocess. As a result, the theoretical calculated values were compared with the CAEanalysis results. The last but not least, modern multi-body dynamic software wasemployed to study on the dynamic characteristics under multi-boundary constraints.The system kinematics and dynamics analysis were done from the chain tension,positive bias, labeled links running track, hydraulic tensioner plunger force, plungerdisplacement five aspects respectively, timing silent chain system was verified from the simulation level. In addition, two methods (test derivation and theoreticalcalculation method) for bench test were introduced, the test results about chain tensionforce of timing silent chain system were comparing with the simulation results toverify the feasibility of the design.The research results provide a strong theoretical support for timing silent chainsystem design, help to improve independent research and design capability on moderngasoline engine timing silent chain drive system, accelerate the establishment of silentchain development and design system, advanced timing silent chain localizationprocess.