Lesson 1.1.3 Gears, Pulley Drives, and Sprockets
In the lesson we learned about how gears, pulley drives, and sprockets work, the calculations for those mechanisms, and the advantages and disadvantages of pulleys and sprockets. Below are pictures of the notes.
Activity 1.1.3 Gears (VEX)
In this activity we were tasked with making a simple gear train and a compound gear train out of VEX materials. After we made the gear trains, we were asked to find the gear ratio of each part of the gear train and the gear ratio for the gear train as a whole for both gear trains. Below are pictures of the calculations and pictures of gear trains that we made. Below that are the conclusion questions we answered for this activity.
Simple Gear Train
Conclusion Questions
1. How many times will gear A rotate compared to gear D? How does this compare to the gear ratio you just calculated in the table? Gear A will rotate once for every time gear D rotates. This aligns with the gear ratio I just calculated in the table.
3. How can you make gears A and D rotate in the same direction? I can make gears A and D rotate in the same direction by placing only one idler gear between them or by placing them on the same axle.
4. What will the gear ratio be if A is connected directly to D? The gear ratio if A is connected to D would still be 1:1.
5. How does the ratio between A and D compare to the entire system? The ratio between A and D is equivalent to the ratio of the entire system.
6. If gear D is the final output, or where the load is attached, then how did gears B and C impact the system? If gear D is the final output, or where the load is attached, gears B and C impact the system as idler gears. This means that technically they aren't needed to find the gear ratio.
4. What will the gear ratio be if A is connected directly to D? The gear ratio if A is connected to D would still be 1:1.
5. How does the ratio between A and D compare to the entire system? The ratio between A and D is equivalent to the ratio of the entire system.
6. If gear D is the final output, or where the load is attached, then how did gears B and C impact the system? If gear D is the final output, or where the load is attached, gears B and C impact the system as idler gears. This means that technically they aren't needed to find the gear ratio.
Compound Gear Trains
Conclusion Questions
1. How many times will gear A rotate compared to gear D? Gear A rotates once for every 5.83 rotations that gear D does.
3.Why might compound gear trains be better than two gears alone? Compound gear trains might be better than two gears alone because you might get a greater mechanical advantage with a compound gear train instead of two gears alone. Additionally, it might better help one complete the same function that they use two gears alone for over a greater distance.
4. Name and describe an application of a compound gear train. An application of a compound gear train is a car's automatic transmission. This mechanism changes gears as the vehicle moves instead of the person driving the car having to manual change gears like with a clutch. The gears change as the speed of the vehicle changes. When you accelerate your car, a torque converter senses this and tells the automatic transmission to shift to a higher gear. When you slow down your car, a torque converter also senses this and tells the automatic transmission to shift to a lower gear.
4. Name and describe an application of a compound gear train. An application of a compound gear train is a car's automatic transmission. This mechanism changes gears as the vehicle moves instead of the person driving the car having to manual change gears like with a clutch. The gears change as the speed of the vehicle changes. When you accelerate your car, a torque converter senses this and tells the automatic transmission to shift to a higher gear. When you slow down your car, a torque converter also senses this and tells the automatic transmission to shift to a lower gear.