| The loader, especially the traits of the wheel loader: excellent flexibility, fast working rate, high efficiency, easy to operate, and so on. Those traits make the wheel loader be suitable for scraping and transporting in mine or construction industry, and suitable for loding and unloading for many fixed facilities, trucks, trains, etc. The wheel loader is widely used in many industries. It has become one of the necessary engeneering tools in modem society.The dring forces between the left and right driving wheel of wheel loader will be well matched when the limited slip differential is used. It can geatly improve the dynamic performance and the passing ability of wheel loader. The limited slip differential that adds limited slip device to the conventional differential is the improved product of conventional differential so as to it can transmit most of the torque or all the torque from the input torque to the other driving wheel. Therefore, the driving wheel can produce enough traction force that can propel the vehicle past the slippery area. Though there are many kinds of LSD, they can be classified three major types:1,Torque sensitive limited slip differential. The limited slip torque which is produced by the friction plates is related to the input torque of the differential. The limited slip torque has increasing functional relationship with the input torque. The greater the input torque, the greater the limited slip torque.2,Speed sensitive limited type differential. The limited slip torque which is produced by the fluid is associated with the speed of the differential. The limited slip torque has increasing functional relationship with speed velocity difference of the half axles.3,Active control limited slip differential. as to this kind of differential, it adds electronic device or electro hydraulic control device on the base of the torque sensing LSD or speed sensing LSD. According to the actual attachment condition of the driving wheel, it can fulfill the control of the limited slip torque. The devices can make the differential work in the best condition.The thesis introduced the structure and the traits of main parts of limited slip differential studied in this thesis, and working principle of limited slip differential. Intruduced how to build the 3D model of the friction plate type differential based on the software CATIA. And transmitted the 3D model built in CATIA into ADAMS by using the interface software of CATIA and ADAMS.What's more, the paper introduced the software ADAMS and the virtual prototype technology. After accomplishing the transmission, added the restriction and the load to the system, and chose the impact-contact parameters of the gears, at last built the whole virtual prototype model of friction plate type differential. Also I simulated the model for 7 working conditions such as straight driving on compacted soil road and asphalt pavement, steering on the muddiness pavement and freezing pavement. By means of simulation analysis, the validity of kinematic characteristics of the virtual prototype model was verified. Moreover, I got the some data closely related to the working performance such as LSD's input torque and output torque, friction torque produced by the friction plates. These data could be used in the analyzing of the friction plate type LSD.According to calculation, the working range of the LSD's bias ratio and locking ratio can be got in theory. Through the data got in the simulation, the actual bias ratio and locking ratio of the LSD can be calculated. Compared the theoretic working range with the actual value, the working performance of the friction plate type LSD can be evaluated. The actual bias ratio is about 1.83, the actual locking ratio is about 0.294, these data illuminated that the LSD researched by this thesis can meet the requirement of the wheel loader.The thesis also from the perspective of transmission theory analyzed the parameters affected the working performance of the friction plate type LSD. Made clear how the parameters affect the working performance of the LSD. This can be helpful to the further research of the LSD. The conclusion listed as follow:The working performance of the friction plate type LSD is only related to its structure characteristics. As long as the structure of the friction plate type LSD is confirmed, the locking ratio and the bias ratio are confirmed. That is, the working performance of the friction plate type LSD is confirmed. The locking ratio is in proportion to the number of the friction plates'working face, the friction coefficient of the friction plate, active friction plates'equivalent radius and the V-groove's angle. The locking ratio is in inverse proportion to the actuator's equivalent radius. Therefore, if we want to improve the working performance of the friction plate type LSD, we should proceed with the number of the friction plates'working face, the friction coefficient of the friction plate, active friction plates'equivalent radius, the V-groove's angle and the actuator's equivalent radius.1,The influence of the friction plates'working face number on the bias ratioAs far as the friction plate type LSD is concerned, the working face number is determined by the number of the friction plate and the reaction plate. If the number of the plate is increased, the number of the working face is increased. Therefore, the friction torque and the bias ratio increased.2,the influence of the fiction plate's friction coefficient on the bias ratioThe friction coefficient reflects the working state between the friction plate and the reaction plate. The working characteristic of the friction coefficient is affected by surface material and surface temperature of the plates. The greater the friction coefficient, the greater the friction torque and the bias ratio will be.3,the influence of the equivalent radius of the friction plate on the bias ratioThe greater the equivalent radius of the friction plate, the greater the friction torque and the bias ratio will be. The equivalent radius of the friction plate is limited by the assembly space of the large bevel gear and the actuator assembly space. The overall size of the LSD and the torque transmitted by the LSD also inflect the equivalent radius of the friction plate.Finally, process strength analysis of spider shaft and reaction plate, reseach the strained condition of them, and study how the chamfer affects the stress distribution.
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