Worm Gears

The worm gears are widely used for transmitting power at high velocity ratios between non-intersecting shafts that are generally, but not necessarily, at right angles. It can give velocity ratios as high as 300 : 1 or more in a single step in a minimum of space, but it has a lower efficiency. The worm gearing is mostly used as a speed reducer, which consists of worm and a worm wheel or gear. The worm (which is the driving member) is usually of a cylindrical form having threads of the same shape as that of an involute rack. The threads of the worm may be left handed or right handed and single or multiple threads. The worm wheel or gear (which is the driven member) is similar to a helical gear with a face curved to conform to the shape of the worm. The worm is generally made of steel while the worm gear is made of bronze or cast iron for light service.
 Types of Worms:-
The following are the two types of worms :
1. Cylindrical or straight worm, and
2. Cone or double enveloping worm.
The cylindrical or straight worm, as shown in Fig. 31.1 (a), is most commonly used. The shape of the thread is involute helicoid of pressure angle 14 ½° for single and double threaded worms and 20° for triple and quadruple threaded worms. The worm threads are cut by a straight sided milling cutter having its diameter not less than the outside diameter of worm or greater than 1.25 times the outside diameter of worm. The cone or double enveloping worm, as shown in Fig. 31.1 (b), is used to some extent, but it requires extremely accurate alignment.

Worm & Worm Wheel Gears 

We provide a wide collection of worm and worm wheel gear boxes that are extensively used to reduce rotational speed and are a simple example of a screw. It also allows higher torque to be transmitted. Owing to their compactness, efficiency. Our range of worm and worm wheel gear is largely used to serve various industrial applications.

Our worm and worm wheel gear boxes are extensively used in:

• Presses
• Rolling mills
• Conveying engineering
• Mining industry machines
• Rudders
• Automotive differentials Worm drives protects the vehicle against rollback and boast of higher reduction ratios.