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VR-Pulley

Intended for use with B-ISG and full Hybrid powertrains, IP has produced a new multi-mode crankshaft mounted VR-Pulley technology. This largely passive device which packages within the standard pulley diameter provides all normal pulley functions including a crankshaft torsional damper. The VR-Pulley gives the following functions and benefits.

applications

• B-ISG for gasoline and diesel passenger car engines
• B-ISG for heavy-duty engines
• Improved hybrid regenerative braking
• Simplification of hybrid powertrains through integrated electric ancillary mode

technology

• In normal operation the drive to the pulley is via a one-way mechanism, as with many conventional de-coupler alternator drives. By engaging a simple clutch with and low power solenoid, the drive is transmitted via an epicyclic mechanism containing only simple spur gears creating a ratio that can be tuned to suit specific applications.
• If the clutch is left open whilst the engine is stationary, the pulley is de-coupled from the crankshaft enabling the electrical machine to drive FEAD ancillaries through the belt.

benefits

• Up to 3.5 x reduced electrical machine torque requirement for engine cranking 
• Major reduction in belt tension requirement
• De-coupler function to improve dynamics and prevent belt squeal
• Ancilliary drive mode enabling electrical machine to drive engine ancillaries e.g. A/C compressor, water pump, vac pump etc., whilst engine is stopped
• Re-optimised electrical machine can provide increased regeneration power in comparison to conventional B-ISG machines