The Research Of Pre-load For Main Reducer Of Automobile's Driving Axle And The System Development

Driving taper assembly of automobile's driving axle is a crucial part for the transmission system, and its assembly quality has an important influence on the performance of the whole automobile. The measurement and control about the tightening torque of the spindle nut and the pre-tightening force of the bearing are studied in this dissertation. The main content is as follows:Chapter 1: introduce the basic structure of the automobile's driving axle and assembly technology of main reducer, and two important indexes influencing the quality. Then discuss the situation and development of the technology of the screw tightening and the control of the pre-tightening force of the bearing both at home and abroad.Chapter 2: analyze the force and stiffness of the taper roller bearings. Then study the bearing's pre-tightening theory and give the selecting theory and grouping method of adjustable gaskets based on the assembly size chain.Chapter 3: analyze adjustment theory of axial pre-tightening force, and have a mechanical analysis, which provides for a theory basis for setting up the assembly model and the development of test system.Chapter 4: introduce the structure and theory of the hardware of control system, and study the key technology on how to control the movement and logic.Chapter 5: set up the test system model based on the previous theory analysis and calculation. Introduce the design of the driving system, electrical system and test software system in detail, and discuss the influential factor about measurement error during the acquisition of test data. Consequently take some necessary method to compensate and correct the measurement error in the test software, and ensure the measurement precision.In the end, take a practical assembly on the main reducer Model 320 provided by the customer, which proves the assembly model, hardware and software all feasible.