LOWER LINK OF INTERNAL COMBUSTION ENGINE

A lower link (6) is provided with an oil hole (30) in a crank pin bearing portion (11) in order to supply a jet of oil to a connecting portion between an upper pin (4) and an upper link (3). Oil hole (30) is composed of a first oil hole (31) linearly extending from the inner peripheral surface of crank pin bearing portion (11) outwardly in the radial direction, and a second oil hole (32) linearly extending from the outer surface of lower link (6) so as to intersect a distal end portion of first oil hole (31). An inclination angle (θ) of first oil hole (31) with a divided surface (14) set as a reference becomes relatively small, and hence the position of an oil inlet (31 b) involving a problem of stress concentration becomes closer to divided surface (14) exhibiting a relatively low stress. Consequently, the stress concentration at oil inlet (31b) is alleviated.