上游充通大学 SHANGHAI JIAO TONG UNIVERSITY LECTURE 6-II Planar Linkage Mechanisms 强 a 6 SHANG 1日gG ERSITY
LECTURE 6-II Planar Linkage Mechanisms Planar Linkage Mechanisms
上游充通大学 OUTLINE SHANGHAI JIAO TONG UNIVERSITY Planar Linkages and 4-bar mechanism Transformations of Planar Kinematic Chains Important kinematic characteristics Grashof Condition ME357 Design Manufacturing ll
OUTLINE Planar Linkages and 4-bar mechanism T f ti f Pl Ki ti Ch i Trans formations o f Planar Kinematic Ch ains Important kinematic characteristics Grashof Condition ME357 Design & Manufacturing II
上海充通大 Planar Linkages and 4-bar mechanism SHANGHAI JIAO TONG UNIVERSITY 4-Bar Nomenclature ·Ground link(连架杆) Links pivoted to gound -Crank(曲柄) -Rocker(摇杆) ·Coupler(连杆) length Link 3,length b B Link Coupler P Rocker length Crank Link -length-d Ground Link Pivot 0 Pivot 0 ME357 Design Manufacturing ll
Planar Linkages and 4-bar mechanism 4-Bar Nomenclature • G d li k( Groun d li nk(连架杆 ) • Links pivoted to gound – Crank(曲柄 ) – Rocker(摇杆 ) • Coupler(连杆 ) B Coupler A Crank Rocker Ground Link Link 1, length d Pi t 0 Pi t 0 Crank ME357 Design & Manufacturing II Pivo t 02 Pivo t 0 4
上海充通大 Planar Linkages and 4-bar mechanism SHANGHAI JIAO TONG UNIVERSITY Some definitions: Path Tracer Point Crank(曲柄)-a link 0- which makes a complete Coupler Coupler Curve Link revolution and is pivoted to ground @Rocker(摇杆)-a link 3 which has oscillatory (back and forth)rotation and is pivoted to ground. Input Follower Link Link Coupler (or connecting A rod连杆)-a link which Fixed Link has complex motion and is not pivoted to ground
Planar Linkages and 4-bar mechanism Some definitions: Cran k（曲柄） – a li kn k which makes a complete revolution and is pivoted revolution and is pivoted to ground Rocker （摇杆 ） – a link which has oscillatory (back and forth) rotation (back and forth) rotation and is pivoted to ground. Coupler (or connecting (or connecting rod连杆 ) – a link which has com plex motion and 4 is not pivoted to ground
上海充通大 Planar Linkages and 4-bar mechanism SHANGHAI JIAO TONG UNIVERSITY Types of 4-Bar linkages B Crank Rocker Rocker Crank D A 77777 D A O777 D Crank-rocker Double-rocker Double-crank 曲柄-摇杆机构 双摇杆 Or Drag link 双曲柄 Depend on range of motion of links connected to ground
Planar Linkages and 4-bar mechanism Types of 4-Bar linkages C C B C Crank B B Rocker Rocker Crank Crank A D A D A D Double-rocker 双摇杆 Double-crank Or Drag link 双曲柄 Crank-rocker 曲柄 -摇杆机构 Depend on range of motion of links connected t d o groun d