Analysis by Graphical Methods Limited to Single Instant

Cams 1

Motion Overview

Linkages

Dwell requires indexer

Analysis by graphical methods – limited to single instant

Full cycle requires mathematical function or numerical differentiation

Slider crank functions for position

Differentiate to find velocity and acceleration

Calculus differentiation

Numerical differentiation (below)

4-bar functions for position also available

more complex linkage functions not available (must use Solid Works Models)

Cams

Designed using mathematical functions

Multiple cam sections can be dwell, rise, fall

Engine http://auto.howstuffworks.com/engine1.htm

Design http://www.softintegration.com/chhtml/toolkit/mechanism/cam/cgi_cam.html

Follower Motion Functions

Example page 336

Rise 50 mm in 1.5 s, fall in 2 s, dwell 0.75 s

Estimate the motion using constant acceleration function

Sketch estimated time charts

Sketch estimated displacement plot

Sketch estimated acceleration plot

Estimate maximum velocity and acceleration

Start with position to time function and derive velocity to time and acceleration to time functions

Calculate actual function maximum velocity and acceleration

Pages 331-335

Norton, Design of Machinery

Norton, Design of Machinery

Cyclo Indexer

page 368 9-8

Rise 24mm harmonic in 0.2 s

Dwell 0.3 s

Fall 10mm harmonic in 0.3 s

Dwell 0.2 s

Fall 14mm harmonic in 0.2 s

CAM GEOMETRY