Fundamentals of Gears Explained

Gears: Basic Concepts

1. What are gears and what are they used for?

They are mechanical elements designed to transmit turning movements.

2. What does it mean when two gears "engage"?

It means their teeth fit into those of another similar wheel.

3. What are the two main characteristics of gears? How are they represented?

The two main characteristics are the number of teeth (Z) and the rotational speed (N).

4. What happens if two gears have a different number of teeth? And if they have the same number?

• If they have a different number of teeth, the smaller gear rotates faster than the larger gear.
• If they have the same number of teeth, they rotate at the same speed.

5. In a pair of gears, what role does the motor gear have? And the output gear?

• The motor gear pushes or drives the movement.
• The output gear receives the movement.

6. Depending on their shape, what types of gears are there?

• Cylindrical gears
• Conical gears

7. What is the difference between a gear with straight teeth and one with helical teeth?

Gears with straight teeth follow straight lines, while gears with helical teeth have curved teeth.

8. What does it mean when two gears reverse the rotational direction?

It means the motor gear rotates clockwise, and the driven gear rotates counter-clockwise.

9. What is an idler gear? And a gear train? What are they good for?

• An idler gear is used to reverse the rotational direction between the input and output gears.
• A gear train is a mechanism formed by more than two gears.
• They are useful for achieving desired speed ratios, torque changes, or maintaining the same rotational direction (with an odd number of gears including the idler).

10. What is a two-gear speed reducing mechanism?

In a speed reducing mechanism, the motor gear is smaller than the output gear. The output gear turns more slowly but is able to transmit more force (increase torque).

11. What characteristics does a two-gear speed multiplier mechanism have?

In a speed multiplier mechanism, the motor gear is bigger than the output gear. The output gear rotates faster but transmits less force (decreases torque).

12. What is a compound gear? What is it used for?

A compound gear consists of two gears of different sizes joined together on the same shaft, so they rotate at the same speed. Compound gears are used in gear trains to achieve larger speed reduction or multiplication ratios in a compact space.

(Note: The original text mentioned accompanying this explanation with a drawing, which is not possible in this format.)

13. What does it mean when gears transmit movement accurately? What advantages and disadvantages can this feature have?

When gears transmit movement accurately, it means they cannot slip relative to each other.

(Note: The original text indicates this answer is incomplete - "PREGUNTALE A OTRO YO NO LA ENCUENTRO" which translates to "Ask someone else, I can't find it".)