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Development of a novel alternator pulley for reduction of engine noise and vibration is described in detail. The sources of noise and vibration resulting from interaction of the alternator's apparent inertia with the speed variation of the engine crankshaft are discussed and quantified as they relate to decoupling of this vibration from the alternator rotor. Present approaches to improving the noise and vibration as well as reducing the wear and stress on accessory drive belts are discussed as background to the discussion of the controlled decoupling pulley. The new pulley is described in detail, including its working principal, part configuration details, and both static and dynamic characteristics compared with competitive pulleys, followed by details of the development phases.

Epilogics, a young engineering firm in Los Gatos, CA, has developed the first fully geared, high torque, high efficiency, infinitely variable transmission suitable for automotive applications. The IVT has particular significance to electric vehicles because it can provide a highly efficient, yet exceptionally controllable means to regenerate power throughout the normal braking cycle (allowing regeneration even at near-zero vehicle speeds). Under normal operating conditions, the efficiency of the Epilogics transmission exceeds 90% as derived mathematically and corroborated experimentally. The device does not rely on traction to transmit torque and can therefore match the torque capacity of any typical gear drive. The size, weight, and cost of the device closely approximates that of a four-speed transmission suitable for the application.

Epilogics, a young engineering firm in Los Gatos, CA, has developed the first fully-geared, high torque, high efficiency, infinitely variable transmission (IVT) suitable for automotive applications. To prove its torque capacity, Epilogics demonstrated a prototype of its patented transmission concept in a Class VII diesel truck in June, 1989. In addition to being ideally suited as a transmission for motor vehicle drivetrains, the IVT can provide a means to efficiently and flexibly drive engine accessories independently of engine speed. Products have already been designed or built to drive alternators at a constant speed (irrespective of engine/vehicle speed) and to control cooling fan speeds independently of engine/vehicle speed. Outside of automotive applications, experimental designs of automatically adjusting manual sailboat winches and continuously variable bicycle transmissions have been implemented.