08/08/2025
# # # **1. Spur Gear**
**Design**: Straight teeth parallel to the gear axis.
- **Use**: Simple, efficient, and commonly used in low-speed applications (e.g., clocks, conveyors).
**Limitation**: Noisy at high speeds due to sudden tooth engagement.
# # # **2. Straight Gear**
**Note**: This likely refers to **spur gears** (same as above).
# # # **3. Spiral Gear**
**Design**: Curved teeth resembling a spiral (similar to helical gears but with a more pronounced curve).
**Use**: Smoother engagement than spur gears, often used in high-load applications.
# # # **4. Worm Gear**
**Design**: A screw-like worm meshing with a worm wheel.
- **Use**: Provides high torque reduction and self-locking (e.g., elevators, conveyor systems).
**Advantage**: Compact and allows large speed reductions.
# # # **5. Helical Gear**
**Design**: Teeth cut at an angle to the gear axis (helical shape).
**Use**: Smoother and quieter than spur gears, used in automotive transmissions.
**Disadvantage**: Produces axial thrust, requiring thrust bearings.
# # # **6. Herringbone Gear (Double Helical Gear)**
**Design**: Two helical gears with opposing angles (V-shape), canceling axial thrust.
**Use**: Heavy-duty applications like turbines and large machinery.
# # # **7. Planetary Gear (Epicyclic Gear)**
**Design**: Central sun gear, planet gears, and an outer ring gear.
**Use**: High power density, used in automatic transmissions and robotics.
- **Advantage**: Compact with multiple speed ratios.
# # # **8. Hypoid Gear**
**Design**: Similar to spiral bevel gears but with non-intersecting axes.
**Use**: Common in automotive differentials for rear-wheel drives.
- **Advantage**: Stronger and quieter than straight bevel gears.
# # # **9. Internal Gear**
**Design**: Teeth on the inside of a cylinder, meshing with a smaller external gear.
**Use**: Planetary gear systems and compact gear trains.
# # # **10. 2 Helical Gears**
**Note**: Likely refers to a pair of helical gears meshing together.
# # # **11. Rack & Pinion**
**Design**: A linear rack (straight bar with teeth) meshing with a pinion (small gear).
**Use**: Converts rotational motion to linear motion (e.g., steering systems in cars)
