Fem: timing-belt pulley

Three-part timing-belt pulley constructed of steel and aluminium. After value engineering: moulded plastic product. Strength calculations of plastic design justified investment in plastic mould. Extra advantage: noise reduction.

Transfer force: 18.9 Nm. Only possible when powergrip tooth shape of belt and pulley are within specification. Precise tooth form achieved in 3 measurement and correction steps within the mould.

Highest stress at point where 5MR teeth meet the boss. Resulting stress: 14.4 N/mm2. Maximum load-carrying capacity: PA6 30% glass filling at 70°C is 15 N/mm2 at joint. This is not located at point of highest stress. Maximum allowable stress is therefore 28 N/mm2. This results in an acceptable safety factor of 1.9.