10-02-2012, 03:05 PM
DYNAMIC ANALYSIS OF CAM MECHANISM
DYNAMICS EXPERIMENTS.docx (Size: 463.18 KB / Downloads: 89)
Introduction
Cam is a machine member that transmits the particular motion to the follower by direct contact. Various cams and followers are used in practice. Some of the cam types are radial cam, circular cam, eccentric cam and tangential cam. Some of the followers are flat faced follower, mushroom faced follower and roller follower. The cam jump speed phenomenon can be observed by adding dead weights over the follower.
Experimental Procedure
a) Profile of Cam
i) The circular cam is mounted on the cam shaft and flat-faced follower is attached at the end of push rod.
ii) The circular protractor is set at the desired position and the weight seat and dial gauge were set in position.
iii) Cam is rotated by hand and the dial gauge readings are noted down for every 10 interval.
iv) The displacement diagram is plotted on a linear graph with suitable scale against the cam angle.
v) Finally from the cam displacement the cam profile is drawn.
b) Phenomenon of jump speed
i) The displacement dial gauge is removed from the apparatus and the power supply is switched on.
ii) Speed of the motor is slowly increased. At a particular speed an anonymous striking sound is heard. The speed at which this sound is heard is called jump speed.
iii) Use of cam and follower system beyond this speed is useless because the desired path on the cam is not followed.
Inference
When the load on the follower increases the jump speed decreases.
Result
1. The profile of the cam was drawn by using the displacement curves.
2. The phenomenon of jump speed was studied.