Question

Identify any major external and internal forces that you can expect to be present on the mechanism inside the jigsaw power tool (gears and scotch yoke component). Does turning the blade or twisting by the user change the forces? How has the design been supported against these forces?

Answer 1

jigsaw power tools are mainly used curved cuts in materials such as wood,metal and plastic.They can also do plunge cuts.Motors are the main component which converts the electricity into motion.The longer the stroke length of the jigsaw, the more efficient is the jigsaw.

Jigsaw power tools has either a clamshell housing or a jampot housing.The housing of more powerfull jigsaws are comprised of aluminium.The handle is the component of the jigsaw which is used to guide the tool along the cut.Jigsaw blades are generally made of either high carbon steel or high speed steel.

External and internal forces acting on the machine parts can be classified as

a) dead weight forces

b) friction forces

c) inertia forces

d) centrifugal forces

e) forces generated during power transmission

Mechnical design phase is very imortant from the view of designer as whole design process depends on correct design of problem.

Preliminary alternatives are eliminated during this phase.Physical properties of mateial,loads stress,deformation and failure should be known by the designer.

Turning and twisting may change the forces.