Motion Flashcards
What type of motion goes in one direction only?
Linear motion
What type of motion goes back and forth?
Reciprocating motion
What type of motion goes in circles?
Rotary motion
What type of motion swings back and forth?
Oscillating motion
What does a mechanism have?
- an input, process and output
- the ability to change direction in which a force acts
- the ability to change the size of the force
- the ability to change the place where the force acts
An input of a mechanism is….
The change of condition that will influence the output
The process of a mechanism is….
The transfer of information provided by the input to the output
The output of a mechanism is….
A predictable end result produced by the input
What is a class one mechanism?
Load Effort
_______________________
Fulcrum
Example : the workman uses the trolley to carry the load
What is a class two mechanism?
. Effort
________________________________
Fulcrum Load
Example : the gardener uses the wheelbarrow to carry the load
What is a class three mechanism?
. Effort
__________________________________
Load Fulcrum
Example : the fisherman catches the load
What does one cycle mean?
One rotation/revolution of the CAM
What does dwell mean?
When the CAM rotates but the follower doesn’t rise or fall
What does rise mean?
The part of the CAM that causes the follower to rise
What does fall mean?
The part of the CAM that causes the follower to fall
What are the different types of cam profiles and what do they mean?
Pear - follower is motionless then rise and falls
Eccentric - produces smooth motion
Snail - follower rises then suddenly drops
Heart - allows rise and fall
What are the types of belts and their advantages?
Round belts - can turn through 90 degrees
Toothed belts - low chance of slippage
V belts - greater drive because more surface area touches the pulley
What are the different types of gears and their descriptions?
Spur gears - transmit rotary motion on parallel shafts
Bevel gears - transmit motion through right angle
Worm and wheel - used to reduce speed, worm is always the driver
Rack and pinion - changes rotary to linear motion
Sprockets and chains - transmits motion through 2 gears, not touching but using a chain
What is the equation for calculating the gear ratio?
Number of teeth on the driver
——————————————
Number of teeth on the driven
What is an idler gear used for?
To make the driver and driven gears turn in the same direction
