DESIGN AND ANALYSIS OF WORM PAIR USED IN SELF-LOCKING SYSTEM WITH DEVELOPMENT OF MANUAL CLUTCH

Abstract

Mostly in material handling equipment gear drives are used. In these systems when the driving torque is suddenly decreased due to power off or any mechanical failure at the input shaft of the system, then gears will be rotating either in the same direction driven by the system inertia, or in the opposite direction driven by the resistant output load due to gravity, spring load, etc. The latter condition is known as back driving. However, there are also solutions in gear transmission that prevent inertial motion or back driving using self-locking gears without any additional devices. Self-locking is the ability of gear system which constitute a drive which gives the input gear the freedom to rotate the output gear in either directions but the output gear locks with input when an outside torque attempts to rotate the output in either direction. Worm gear pair is also a self-locking gear pair but it is having very low efficiency around 40%, when made self-locking. In our project, self-locking property is obtained by using worm pair which is in mesh with each other. This system is simple in construction. The efficiency around 90% can be obtained as compared to 40% of conventional worm gear system.