COMMON APPLICATION Worm and worm gear
Worm and worm gear sets are used in many, everyday products including: electrical mixers, hubometers, right angle speed reducers and medical equipment.
let’s learn about two additional and highly versatile types of gears that are used to transmit motion and power at various speeds and speed ratios: worms and worm gears. A worm is a gear with one or more cylindrical, screw-like threads (also referred to as “starts”) and a face width that is usually greater than its diameter. A worm has a center hole (bore) for mounting the worm on a shaft.
Worm gears, like worms, also are cylindrical and bored for mounting on a shaft. However, unlike a worm, a worm gear’s diameter is usually much larger than the width of its face.
Note:
Worm gears differ from spur gears in that their teeth are somewhat different in shape and are always formed on an angle to the hole (axis) in order to mate with worms. (See Figure 4.1).
In order to transmit motion and power at various speeds and speed ratios, worms and worm gears work in sets, rotating on shafts at right angles to one another. The worm usually drives the worm gear. Accordingly, the worm gear is usually the driven member. (See Figure 4.1A)
Important:
In worms and worm gear sets, both the worm and worm gear are of the same hand. Right-hand sets are considered standard. As a result, right-hand sets will always be furnished unless otherwise specified.
