A Review and Classification of Variable Valve Timing Mechanisms 890674
Mechanisms for internal combustion engine variable valve timing (VVT) have been the subject of almost 800 US patents since 1880. Over 110 of these patents were issued just in the three years 1985 through 1987. Also, many technical papers have been published on VVT mechanisms. We reviewed all of these patents and much of the literature. As a result, we have classified all the mechanisms found into IS basic concepts which we describe and evaluate in this paper.
We conclude that VVT has much potential, but that very little of this potential has yet been realized. Serious difficulties have limited the application of variable valve timing to date. Virtually all VVT mechanisms proposed until recently suffer from high cost and complexity, limited variability, and high impact velocities. An improved system is described in a companion paper (1)*.
Citation: Dresner, T. and Barkan, P., "A Review and Classification of Variable Valve Timing Mechanisms," SAE Technical Paper 890674, 1989, https://doi.org/10.4271/890674. Download Citation
Author(s):
Thomas Dresner, Philip Barkan
Affiliated:
Stanford University
Pages: 16
Event:
SAE International Congress and Exposition
ISSN:
0148-7191
e-ISSN:
2688-3627
Also in:
100 Years of Engine Developments-PT-115, SAE Transactions Journal of Engines-V98-3
Related Topics:
Variable valve timing
Combustion and combustion processes
SAE MOBILUS
Subscribers can view annotate, and download all of SAE's content.
Learn More »