圈上海人峰 LECTURE 8 Mechanical Design and Manufacturing II Power/Energy Transmission: Power Screws(传动螺旋) Covered: 11-1 and 11-2 in Mechanical Engineering Design 圈上我大峰 Lectures Power/Energy Conversion Power/Energy (Electrical Motors) Transmission Gears,Cam,Linkage Belt Drives, Power Screw) Joints Transmission (Fasteners, Support Connectors) (Bearings) Structural Support (Frames) Tools Statics,Dynamics, Stress Analysis,etc. 2
1 Power/Energy Transmission: Power Screws（传动螺旋） Mechanical Design and Manufacturing II LECTURE 8 Covered: 11-1 and 11-2 in Mechanical Engineering Design 2 Lectures Power/Energy Conversion (Electrical Motors) Transmission Support (Bearings) Joints (Fasteners, Connectors) Structural Support (Frames) Tools Statics, Dynamics, Stress Analysis, etc. Power/Energy Transmission (Gears, Cam, Linkage, Belt Drives, Power Screws)
国上活我人隆 Power Screw Principles! >The screw thread is one of the most important inventions ever made >Power screw using the principle of a screw thread and its mating nut >Used to convert rotation to linear motion >in actuators,production machines(Lead screws)and jacks,etc. >Transmit power,exert the necessary force to move a machine element along a desired path. >Capable of very large mechanical advantages, can lift or move large loads,the speed is often slow 国 上活大学 Power Screw Applicationsl ·Power screws >Either screw can move,as in a jack or >Nut can move,as in a positioning device. servomotor Head Lever 十 coupling Sq.threaded rod lead screw nut-
3 The screw thread is one of the most important inventions ever made Power screw using the principle of a screw thread and its mating nut Used to convert rotation to linear motion in actuators, production machines (Lead screws) and jacks, etc. Transmit power, exert the necessary force to move a machine element along a desired path. Capable of very large mechanical advantages, can lift or move large loads, the speed is often slow. Power Screw Principles1 4 Power Screw Applications1 •Power screws Either screw can move, as in a jack or Nut can move, as in a positioning device
圈上海人峰 NOSEN 餐学 5 圈上大逢 Tong' 二 6
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圈 上濟发大学 Lead Screw and Ball Screw Lead screw(传导螺用 Lead screws are essentially accurate screws used to move a nut attached to a load,and they have been used for centuries to convert rotary motion into linear motion -Lead screws are commonly used on manual economy machine tools Efficiency in a lead screw system may be 30-50% 圈上我大峰 Ball Screws (滚珠螺旋) >Ball screw is similar in function lead screw >Sliding contact between the screw and nut is replaced by rolling contact using recirculating spherical balls,reduce the thread friction,do not suffer from the stick-slip characteristics of sliding joints >Leads to higher efficiency,may have 95%efficiency >However,not self-locking. >Have a more limited fatigue life >But have very high load capacity 8
7 Lead Screw and Ball Screw Lead screw(传导螺杆) • Lead screws are essentially accurate screws used to move a nut attached to a load, and they have been used for centuries to convert rotary motion into linear motion – Lead screws are commonly used on manual economy machine tools – Efficiency in a lead screw system may be 30-50% 8 Ball screw is similar in function to lead screw Sliding contact between the screw and nut is replaced by rolling contact using recirculating spherical balls, reduce the thread friction, do not suffer from the stick-slip characteristics of sliding joints Leads to higher efficiency, may have 95% efficiency However, not self-locking. Have a more limited fatigue life But have very high load capacity Ball Screws（滚珠螺旋）
圈 :上济充大学 Ball Screws (滚珠螺旋) >Modern machine tools,automation equipment,and actuators on aircraft use ball screws for high precision, high efficiency,fast response,and smooth operation. Rotary Encoder ☒☒ ☒ AC Brushless Motor Flexible Coupling Rearing Housing Ballscrew Ballnut Support Bearings 9 chenn.cn
9 Ball Screws（滚珠螺旋） Modern machine tools, automation equipment, and actuators on aircraft use ball screws for high precision, high efficiency, fast response, and smooth operation. 10