Patent ID: 7121251
Filing Date: 2006-10-17
Classification: F02B,F16C,F16H

Abstract:
1. A multi-link piston crank mechanism for an internal combustion engine, comprising: a crankshaft including a crank pin and a pair of crank webs connected with each other through the crank pin; a pair of thrust surfaces formed on the crank webs so as to be opposed in a direction of a center axis of the crank pin; a first link pivotally supported on the crank pin; a second link coupled to the first link; and a connection pin located in a space between the thrust surfaces such that axial end surfaces of the connection pin are opposed to the thrust surfaces, the connection pin connecting the first link and the second link so as to permit relative pivotal motion of the first link and the second link, the connection pin being moveable about the crank pin to form a circular trace, wherein the thrust surfaces extend along the circular trace formed by the connection pin, and the end surfaces of the connection pin and the thrust surfaces come into mutual contact to prevent the connection pin from falling out of the space between the thrust surfaces; and wherein the connection pin includes an axially central portion slidably disposed within a pin insertion hole formed in the first link, and axially opposed end portions slidably disposed within pin insertion holes formed in the second link.