Tham khảo tài liệu 'sổ tay tiêu chuẩn thiết kế máy p50', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | __CHAPTER 43_ FLUID POWER SYSTEMS AND CIRCUIT DESIGN Russ Henke RE. Russ Henke Associates Elm Grove Wisconsin PRESSURE PLOTS FLOW PLOTS POWER PLOTS CYCLE PROFILE CIRCUIT DESIGN OPEN-LOOP AND CLOSED-LOOP CIRCUITS CONSTANT-FLOW VERSUS DEMAND-FLOW CIRCUITS OPEN LOOP DEMAND-FLOW CIRCUITS HYDRAULIC VERSUS PNEUMATIC SYSTEMS PNEUMATIC CIRCUITS EFFECT OF FLUID CHARACTERISTICS ON ACTUATOR PERFORMANCE EFFECT OF FLUID CHARACTERISTICS ON CONTROL-VALVE PERFORMANCE BASIC PNEUMATIC POWER CIRCUIT FLUID LOGIC SYSTEMS REFERENCES GLOSSARY OF SYMBOLS a Acceleration A Area C Coefficient e Efficiency F Force or load g Acceleration due to gravity H Power Ln Normal force component m Mass N Normal force speed p Pressure Q Flow rate STANDARD HANDBOOK OF MACHINE DESIGN S Actuator stroke t Time T Torque v Velocity V Volume W Weight Y Specific weight 0 Angular velocity p Coefficient of friction co Angular velocity Fluid power technology is one of the three primary energy transmission technologies used throughout industry the defense community agriculture and all aspects of productive activity in the industrialized world. In addition to fluid power there are electric and mechanical systems. This chapter deals with the design of hydraulic and pneumatic systems by using the cycle-profile plotting techniques discussed in Chap. 42. PRESSURE PLOTS The pressure plots are the same as the load plots discussed in Sec. except for the introduction of a constant reflecting the interface area over which the load is distributed. The equation is P Ap Note that the constant 1M is different for each size of cylinder. Once the load and pressure plots have been completed the level of energy transfer occurring throughout the machine cycle has been defined. FLOW PLOTS The next step is to define the rate of energy transfer .
