液压与气压传动8英文版_.ppt

Chapter 8 Examples of Hydraulic Systems Find out the working principle for a given set of machine or apparatus and understand the performance of the desired function for speeds and pressures and directions during the machine working periods; Read the preliminary sketch of the hydraulic system ,classified into several basic hydraulic circuit units by actuators; Analyze respectively the principles of several basic circuits and find out the relationship between basic circuits to tidy up the lines; 4. Safety of operation 5. Efficiency of operation 6. Sum up and comprehend the features of the hydraulic system based on the functions of several basic hydraulic circuits mentioned above. Table of contents (4 Examples) 8.1 Hydraulic System of Power-Slipway for Combined Machine Tools 8.2 Hydraulic System for Plastic Injection Moulding Machine 8.3 Hydraulic System of YA32-200 Type Four Column Universal Press Machine 8.4 Hydraulic System of Manipulators 8.1 Hydraulic System of Power-Slipway for combined Machine Tools 8.1.1 Introduction 1.Quick feed 2. Working feed 1 3. Working feed 2 4. End block dwell 5. Quick retract 6. Stop at the start position 8.1.3 Characteristics 8.2 Hydraulic System for Plastic Injection Moulding Machine 8.2.1 Introduction The injection moulding processing is shown below: 8.2.2 Operating principle of hydraulic system of SZ-250A type plastic injection moulding machine 1. Safety gate close 2. Close the mould-chamber The process of mould-chamber is closed experiences the 4 stages. （1）Closing the mould-chamber slowly (2YA＋、3YA＋). (2) Close the mould-chamber quickly (1YA＋、2YA＋、3YA＋). (3) Low pressure and slow speed (2YA＋、3YA＋、13YA＋). (4) High pressure (2YA＋、3YA＋). 3.Injection seat moves onwards （2YA＋、7YA＋） 4. Injection It experiences two stages, i.e., injecting slowly and quickly. (2) Inject quickly （1YA＋、2YA＋、7YA＋、8YA＋、10YA＋、12YA＋） 5. Holding pressure （2YA＋、7YA＋、10YA＋、14YA＋） 6. Pre-plastic （1YA＋、2YA＋、7YA