US Patent 7335122 Low modulus belt for automotive applications

A low modulus drive belt for an automotive accessory drive system is disclosed that allows for relatively high elongation during installation and that maintains a relatively high percentage of its install tension throughout the useful life of the belt. In addition, an automotive accessory drive system is taught that utilizes such a belt as is a method for constructing such a belt. According to one aspect an accessory drive system for an automobile is provided that includes: (a) a drive pulley; (b) an accessory pulley operatively coupled to an accessory drive shaft; and (c) an endless drive belt engaged between the drive pulley and the accessory pulley, where the drive belt includes an endless band of rubber composite material having a plurality of circumferentially extending an axially aligned polyamide 6.6 twisted cords formed therewithin.