MILWAUKEE ELECTRIC TOOL

SLIDER-CRANK ANALYSIS AND TEST

Khaled Alaassmi and Majid Al Qutaim

Project Goal

The goal of the project is to determine the offset that provides the best cutting performance for M-18 Sawzall.

Cutting GeometryA=12.2mm= 0.4803 inB= 56.9 mm= 2.24 inC= 19.812 = 0.78 in

A C

B

Angle = z

Pin A

XOut

Drive Gear

Direction of Rotation

C = Offset

Displacement Analysis of Offset Slider Crank Mechanism Using a Vector Loop Closure Equation:O2A = O2D + DB + BA

D

a

bc

Velocity Analysis Equations

Acceleration Analysis Equations:

Analysis using the “Linkages” software from Robert L. Norton, Design of Machinery, 5ed

Analysis using linkages software

Linkage software was used to make the analysis at 3 different offsets

Offset of 0.78 in Offset of 0 in Offset of -0.78 in

Analysis Using Linkages Software

At an offset of C=0.78 in

Analysis Using Linkages Software

At an offset of C=0 in

Analysis Using Linkages Software

At an offset of C = -0.78 in

Designing Slider Crank Using Pro-Engineer Wildfire 5

Pro E Analysis

At offset of C= 0.78 ”

Pro E analysis

At offset of C= 0 ”

Pro E analysis

At offset of C= -0.78 ”

Physical Testing

Physical Testing

2 different offsets 10 runs each offset At an offset of 0.78 in and 0 in The average cutting time for each offset

was calculated Test was performed on 2 x 4” wood. The applied load on the blade was 7.4 lb

Physical testingCutting performance = Time required to cut through 2x4 pine board

At C = 0 in, Tavg = 8.9 s, sd= 1.4

At C = 0.78 in, Tavg = 6.3 s, sd= 0.3

Recommendation

Use the Prototype Fixture to Design a Metal Fixture.

Acknowledgements

Roger Neitzell Milwaukee Electric Tool Corporation

Questions ?