Research On Constant Pressure Grounding Control System Of Cold Milling Machine Scraper Blade

The cold milling machine, one of the most important machine in the maintenance machinery of asphalt pavement, is mainly used in clearing away the upheaval, oil streak, reticulated mottles and rut of asphalt pavement, and also excavating groove, roughing cement pavement and cutting the dislocated road. During the process of working, the machine depends on scraper blade for compressing the milling groove to recover the scrap material and throw it to the lorry by the belt conveyer. The ground contact pressure of the scraper blade directly affects the scrap material recovery, the milling groove smoothness and the working resistance. If the numerical value is a little bigger or smaller, there will be to have a great influence on the working quality and the working efficiency. Consequently, a detailed analysis about the reasonable value of the ground contact pressure of the scraper blade and constant pressure grounding control strategy are done in this thesis.On the basis of working characteristics and the working requirement, the formative principle of the scraper blade ground contact pressure and working resistance is discussed, The corresponding computation module is set and the calculating formula of the scraper blade ground contact pressure and scraping resistance are derived. Then the reasonable value is calculated and the relation among the ground contact pressure, the scraper blade dead weight and lift cylinder applied force is analyzed In addition, the scraper blade working condition is concluded into three types and the corresponding pressure values are figured out separately. By means of analyzing the extant scraper blade structure and control system and the reasonable value, several projects are designed to enhance the scraper blade working quality.In accordance with the compared result of designed projects and the ground contact pressure value of the specific machine, the optimal project is determined to design. Later, it could be proved by AMEsim simulation and experiment. The research of the paper provides the theory basis for designing and controlling the cold milling machine, and has significance in both theory and practice for improving the workability and the working quality.