A Study of a Variable Compression Ratio System with a Multi-Link Mechanism NISSAN MOTOR CO., LTD

Format:

Conference/Event

Author/Creator:

Moteki, Katsuya, author.

Conference Name:

SAE 2003 World Congress & Exhibition (2003-03-03 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2003

Summary:

This paper presents a variable compression ratio (VCR) system that has a new piston-crankshaft mechanism with multiple links. This multi-link mechanism varies the piston position at top dead center (TDC), making it possible to change the compression ratio of the engine continuously. Previous attempts have been made to achieve variable compression ratio with this type of method, but it was difficult to avoid various undesirable effects such as an increase in the engine size, substantial weight increases, increased engine block vibration due to a worsening of piston acceleration characteristics and increased friction resulting from a larger number of sliding parts. At the stage of developing the basic design of the multi-link geometry, emphasis was placed on selection of a suitable link geometry and optimization of the detailed dimensions with the aim of essentially resolving these previous issues. As a result of the studies conducted at that stage, a VCR link geometry was found that optimally resolves these various issues. Besides achieving the desired VCR capability, this VCR system also provides several new and additional benefits including:The basic characteristics of a prototype VCR engine that incorporates these new benefits are described on the basis of a theoretical analysis and experimental results obtained in tests conducted with the prototype engine

Notes:

Vendor supplied data

Publisher Number:

2003-01-0921

Access Restriction:

Restricted for use by site license