DT Flashcards
(20 cards)
define an mechanism
a mechanism is a device designed to transform
input forces and movement into a desired set of
output forces and the movement.
what are the 4 types of motions and their meaning
Rotary motion =
0bject rotates
Reciprocating motion =
0bject moves back and forth or up and down
Linear motion =
0bject moves in a straight line
0scillating motion = 0bject swings backwards forwards and up and down
name 4 cams and their shape,
Pair: an egged shaped cam
Circular: a circle shaped cam
snail: a heart shaped cam
Drop: a half oval with a drop on top creating a half circle
what is a cam and followers
A cam is a rotating part with a special shape that controls the movement of a follower.
what are levers and their job
A lever is a bar that turns around a fixed point called a fulcrum to move a load with less effort.
what is a class 1 Lever and give an example
A Class 1 Lever has the fulcrum in the middle, with the load on one side and the effort on the other. (Seesaw)
what is a class 2 Lever and give an example
A Class 2 Lever has the load in the middle, with the effort on one side and the fulcrum on the other. (Wheel barrow)
what is a class 3 Lever and give an example
A Class 3 Lever has the effort in the middle, with the load on one side and the fulcrum on the other. (Tweezer)
what is a linkage and what are they for
A linkage is a system of connected levers that can change the direction or type of movement.
what are the 4 linkages type and their motion
Reverse Motion Linkage: Changes linear motion to the opposite direction.
Bell Crank Linkage: Changes motion by 90 degrees (e.g., vertical to horizontal).
Sliding Linkage: Moves parts in a straight line along a track.
Parallel Motion Linkage: Keeps two levers parallel, both move in the same direction.
what are gear trains and their job
Gear trains are two or more gears connected together to transfer motion and force from one part of a machine to another.
what are gear ratios and their job
Gear ratio is the comparison of the number of teeth on two connected gears Controlling speed and torque in a gear system
what are Pulleys and belt and define their job
Pulleys are wheels with a grooved rim that a belt fits around.
A belt is a flexible loop that connects two or more pulleys.
Transfer rotary motion from one pulley to another
Change the direction of motion
Change speed and torque between pulleys depending on their size
Allow motion to be transmitted over a distance
what are compound, Idler and output gears
Compound Gears: Two or more gears fixed together on the same shaft, so they rotate together. Used to achieve bigger changes in speed or torque within a small space.
Idler Gears: Gears placed between the driver and driven gears to change the direction of rotation without affecting the gear ratio.
Output Gears: The gear at the end of a gear train that delivers the final motion or force to do the work.
