This presentation summarizes cams with specified contours and provides examples of tangent cams with reciprocating roller followers. It was submitted by three mechanical engineering students at Gandhinagar Institute of Technology. The document defines cams and followers as a higher pair that can provide reciprocating or oscillating motion. It then discusses cams with specified contours where the cam profile is defined to produce a desired follower motion profile. As an example, it examines tangent cams where the flanks are straight and tangential to the base and nose circles. Expressions are derived for the displacement, velocity, and acceleration of the follower roller in two cases: when in contact with the straight flanks and when in contact with the nose circle

1. PRESENTATION
ON
CAMS WITH SPECIFIED CONTOURS
GUIDED BY:- Prof. Hardik Patel
Kinematics of Machines
SUBMITTED BY:
HIMANSHI GUPTA(140120119057) / ME / A1
PRACHI SHARMA(140120119216) / ME / A1
VIDISHA VYAS(140120119253) / ME / A1
(2131906)
GA N D H IN A GA R IN STITU TE OF
TEC H N OLOGY

2. INTRODUCTION
• A cam is a rotating machine element which
gives reciprocating or oscillating motion to
another element known as follower
• Cam and follower constitute higher pair
• Cam-uniform speed
• Follower-pre-determined motion

4. CAMS WITH SPECIFIED CONTOURS
• When the follower moves with the specified
motion, the shape of the cam profile thus
obtained is difficult and costly to manufacture
• So cams with specified contours are specified
and motion of follower is determined
• Cam profiles consisting of circular arcs and
straight lines are preferred

5. TANGENT CAM WITH RECIPROCATING
ROLLER FOLLOWER
TANGENT CAM:-
• Flanks of the cam are straight and tangential to
the base circle and nose circle
• Used for operating inlet and exhaust valve of
IC Engines

6. • Two cases for derivation of displacement,
velocity and acceleration expressions:
1. When the roller has contact with the straight
flanks
2. When the roller has contact with the nose
TANGENT CAM WITH RECIPROCATING
ROLLER FOLLOWER

7. • Terms used:
TANGENT CAM WITH RECIPROCATING
ROLLER FOLLOWER

8. • CASE 1: WHEN THE ROLLER HAS
CONTACT WITH STRAIGHT FLANK
Displacement:

9. Velocity is given by:
Velocity is maximum where θ is maximum
This happens when roller just leaves the contact with the straight flank
at G i.e. when θ=ф

10. Acceleration is given by:-

12. • CASE 2: WHEN THE ROLLER HAS
CONTACT WITH THE NOSE
DISPLACEMENT:

14. • VELOCITY

15. • ACCELERATION

16. • The velocity is zero at H and maximum at G
• The acceleration is minimum at H and
maximum at G