SCHOOL OF ENGINEERING

DEPARTMENT OF MECHANICAL ENGINEERING

MSE-I (Project)

Topic- Whitworth Quick Return Mechanism

Group No. 14

Sec B

Submitted To- Submitted By-

Dr. Sudeep Sharma Parvesh Taneja 130020201057

(HoD) Rijul Jain 130020201064

Index

1.Introduction- Definition and Terms related to Mechanisms

2.Theory- Whitworth Quick Return Mechanism (Details)

3.Material Required

4.Tools Required

5.Application of Whitworth Mechanism-

Shaping Machine

6.Bibliography

Fig.: Model of Quick Returning Mechanism

1.Introduction-

Definition and Terms related to Mechanisms

A mechanism is a combination of rigid or restraining

bodies so shaped and connected that they move upon each

other with a definite relative motion. A simple example of

this is the Whitworth Quick Return Mechanism used in

shaper machine.

The various parts of mechanism are called links or

elements. Where two links are in contact and relative

motion is possible, then they are known as a pair.

An arbitrary set of links which form a closed chain that is

capable of relative motion, and that can be made into a

rigid structure by the addition of a single link, is known as

a kinematics chain.

To form a mechanism from a kinematics chain one of the

links must be fixed. However as any of the links can be

fixed, it follows that there are as many mechanisms as

there are links in the chain. The technique of obtaining

different mechanisms by fixing the various links in turn is

known as inversion.

2. Theory-

Whitworth Quick Return Mechanism (Details)

The 'Whitworth' quick return mechanism converts rotary

motion into reciprocating motion, but unlike the crank and

slider, the forward reciprocating motion is at a different rate to

the backward stroke. At the bottom of the slotted arm, the peg

only has to move through a few degrees to sweep the arm from

left to right, but it takes the remainder of the revolution to bring

the arm back. This mechanism is most commonly seen as the

drive for a shaping machine.

Fig-Whitworth Quick Mechanism

Whitworth Quick Mechanism is a good example of four bar

mechanism

o The circular rotating disk is called the Crank.

o The link connected to the rotating disk is called Slider.

The crank is also the input drive, it gives the rotational motion

and the slider results in rocker motion, which further results in

the motion of the 3rd linkage i.e. to and fro motion.

o Basic differences between crank and slotted lever mechanisms

and a Whitworth quick return mechanism is the path of

return.

o In whitworth mechanism, the forward travel is different

arc, and returning is a different arc( a smaller circle).

Whereas in crank and slot mechanism, the forward and

backward, both are via a same arc hence take same time

to traverse.

o Whittworth is usually used where arc / path of return is

usually not fruitful.

Like, where angle of blade cutting in only one direction.

In another direction, it just had to return to original point,

without doing any cutting.

3. Material Required-

S.NO. Material Quantity

1. Nails 8-10

2. Nuts & Bolts 4-5

3. Ball Bearing 2

4. Washers 8-10

5. Fevicol (Glue) 200 ml

6. Wood N/A

4. Tools Required-

S. NO. Tool Name

1. Hammer

2. Mallet

3. Chisel

4. Plier

5. Files

5. Application of Whitworth Mechanism-

Shaping Machine

A quick return mechanism is used where there is a need to

convert rotary motion into reciprocating motion. As the disc

rotates the black slide moves forwards and backwards. Many

machines have this type of mechanism shaping machine is the

best example.

Fig-Shaping Machine

A shaper is a type of machine tool that uses linear relative

motion between the work piece and a single-point cutting tool

to machine a linear tool path.

• It’s a machine that can make slots and grooves using a thin

cutting tool

• The linear cutting motion is provided by the “Quick-

Return Mechanism“.

6. Bibliography

S.No Link 1.. https://www.bhavyamachinetools.com/shop/tool-

room-

machine/shapingmachine.html?gclid=CPXHlJmrg

MQCFQeSjgod-oUAmg

2. https://www.wisc-online.com/learn/career-

clusters/stem/eng20704/quick-return-mechanism-

velocity-calculations

3. http://www.quora.com/What-are-differences-

between-crank-and-slotted-lever-mechanisms-and-

a-Whitworth-quick-return-mechanism