Spur gears are also known as which type?

• A. Straight-Cut gears
• B. Helical gears
• C. Bevel gears
• D. Worm gears

Answer: (A)

Spur gears have straight teeth that are cut parallel to the gear axis. This straight, parallel tooth arrangement is why they’re known as straight-cut gears. The simplicity of the tooth shape makes them cheap and easy to manufacture, and they work well for transmitting power between parallel shafts with efficient, direct engagement. However, because the teeth come into contact all at once, they can produce more noise and vibration at higher speeds. Other gear types differ in tooth geometry and shaft arrangement: helical gears use angled teeth for smoother engagement but introduce axial thrust; bevel gears are used for intersecting shafts with conical teeth; worm gears involve a worm and a wheel to achieve high reduction with nonparallel axes.