Two-Stage Variable Compression Ratio with Eccentric Piston Pin and Exploitation of Crank Train Forces

Karsten Wittek; Christof Tiemann; Stefan Pischinger

doi:10.4271/2009-01-1457

2009-04-20

Two-Stage Variable Compression Ratio with Eccentric Piston Pin and Exploitation of Crank Train Forces 2009-01-1457

By variation of the compression ratio the fuel consumption of high boosted gasoline engines can be reduced, due to operating with higher compression ratios at low load compared to an engine with fixed compression ratio. The two-stage VCR-system enables a high share of fuel saving potential relative to full variable systems.

Considering a low cost manufacturability and a beneficial integratability into common engine architectures the length-adjustable conrod using an eccentric piston pin in the small eye has proved as the best concept. The adjustment is performed by a combination of gas and mass forces.

This article describes the design of such a two-stage VCR-system as well as the functional testing under motored and fired engine operating conditions.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Digital $37.00 Print $37.00

Preview Document

We also recommend:

Standards

SAE Mobilus®

Publications

News

Events

Professional Development

A World in Motion (PreK-12)

Participate with SAE

SAE Membership

Donate

Two-Stage Variable Compression Ratio with Eccentric Piston Pin and Exploitation of Crank Train Forces 2009-01-1457

SAE MOBILUS