Opportunities for P/M in Variable Valve Timing Devices 2004-01-0499
Variable Valve Timing (VVT) is a new technology that provides many opportunities for P/M components. A VVT device (also call VCT, variable cam timing, or cam phaser) allows for the timed relationship between an engine camshaft and engine crankshaft to be changed. Prior to VVT, camshafts were synchronized through gears or timing chains. VVT is applied to the timing sprockets or gears so that the relationship between the toothed element and camshaft are adjusted based on engine variables. Many engines now feature VVT and more are scheduled to employ VVT in the future. There are many different types of VVT devices. The type of VVT device commonly referred to as “vane type” contains inner and outer components that are well suited for P/M manufacture. They will be described and reviewed with respect to manufacture by P/M.