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Automation and Robotics
Activity 2.2a Mechanical Gears Review Coreyon ruffin
Read each question carefully and place your answer in the appropriate space.
Examine the picture of the VEX model below and then answer the first three questions.
1. Name the type of movement used as an input ______
2. The output movement has been changed to ______
3. We call this mechanism a ______
reciprocating______________________.
increase, decrease speed___ movement.
rack and pinion
This is number 4 below- In the belt drive mechanism, what happens when the
belt is crossed instead of open?___
moves in the opposite direction
4. ______________________________________________________
5. In a mechanism, when the input goes from a small gear to an output which is a larger gear, the speed
will __decrease______________ (increase, decrease). When this happens, the amount of torque will
____increase________________ (increase, decrease).
6. When a big gear turns a small one, the output provides more _____speed________________ but less
____torque_____________ than the input.
7. Which of the following mechanisms moved slower, the worm and wheel or the rack and pinion?
________worm and wheel_____________________________
8. Which mechanism transmits rotary motion to reciprocating? _rack and pinion______________
9. The advantage of using a chain drive over a belt drive is ____belt drives are faster and carry
more__________________________________________________________.
10. The advantage of using a belt drive over a chain drive is
________speed______________________________________________________.
11. The purpose of an idler gear is to ___spin in the same direction________________________________.
Use the formula below to determine the answers to questions 12 and 13.
Distance moved by rack = number of input turns X pitch X number of teeth on the gear
Problem: A rack with a pitch of 4 mm is used with a 20-tooth gear.
12. How far will the rack move when the input is given one turn? _80mm_______________________
13. How many turns will be needed to move the rack a distance of 240 mm? ____3____________
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