Sir Joseph Whitworth invented the Whitworth quick return mechanism in the 19th century to convert rotational motion into reciprocating linear motion. The mechanism uses four links - a fixed link, slotted bar, driving crank, and slider - to transform the rotation of a crank into the back-and-forth motion of a cutting tool. As the crank rotates clockwise and counterclockwise, the connected slider moves the tool across its stroke to shape or cut materials. This innovative mechanism is still used today in machine tools like shaper and slotter machines.

1. BY,
AMAR M. BORKUTE

2.  Whitworth quick return mechanism is a mechanism which is used to
transform the rotation motion of a crank or crankshaft to the
rectilinear reciprocating motion of a piston or plunger or ram.
Sir Joseph
Whitworth
 Sir Joseph Whitworth born in Stockport, Cheshire, on the 21
December 1803 invented this noteworthy mechanism which is used
to drive the cutting tool on shaping machines.
 Thus the mechanism bears his name i.e. “Whitworth quick
return mechanism.”

3. WORKING
 In Whitworth quick return mechanism, the link CD (link 2) forming the turning
pair is fixed, as shown in Fig. The link 2 corresponds to a crank in a
reciprocating steam engine
 The driving crank CA (link 3) rotates at a uniform angular speed
 The slider (link 4) attached to the crank pin at A slides along the slotted bar PA
(link 1)

4.  The connecting rod PR carries the ram at R to which a cutting tool is fixed.
The motion of the tool is constrained along the line RD produced, i.e. along a
line passing through D and perpendicular to CD.
 When the driving crank CA moves through an angle α in the Anti-clockwise
direction, the tool moves from the left hand end of its stroke to the right hand
end.
 Now when the driving crank moves through an angle β in the clockwise
direction, the tool moves back from right hand end of its stroke to the left hand
end.

5. Link 3 – Driving Crank
Link 1– Slotted Bar
Link 4 – slider
Link 2- Fixed link
DIFFERENT LINKS OF WHITWORTH QUICK RETURN
MECHANISM

6. ANIMATION OF THE WORKING OF MECHANISM

7.  In Fig,
 Link 1- The Slotted bar
 Link 2 – The Fixed Link
 Link 3 – Driving Crank
 Link 4 – Slider

8. APPLICATION:
1.Shaper Machine

9. 2.Slotter Machine