Abstract: 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 (?) 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 (31b) 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.

Abstract: A lower link (7) is formed of two components by being divided at a dividing surface (14) including the central axis of a crank pin bearing portion (11), the two components including a lower link upper (15) with an upper pin bearing portion (12) and a lower link lower (16) with a control pin bearing portion (13). The dividing surface (14) includes a first dividing surface (14a) located more on the upper link side than the crank pin bearing portion (11) and a second dividing surface (14b) located more on the control link side than the crank pin bearing portion (11). In the lower link (7), the first dividing surface (14a) has a surface roughness larger than a surface roughness of the second dividing surface (14b).

Abstract: A lower link (7) is formed of two components by being divided at a dividing surface (14) including the central axis of a crank pin bearing portion (11), the two components including a lower link upper (15) with an upper pin bearing portion (12) and a lower link lower (16) with a control pin bearing portion (13). The dividing surface (14) includes a first dividing surface (14a) located more on the upper link side than the crank pin bearing portion (11) and a second dividing surface (14b) located more on the control link side than the crank pin bearing portion (11). In the lower link (7), the first dividing surface (14a) has a surface roughness larger than a surface roughness of the second dividing surface (14b).

Abstract: A hybrid vehicle includes an internal combustion engine and a motor generator, wherein the internal combustion engine includes a variable compression ratio mechanism structured to vary in mechanical compression ratio depending on variation in position of a compression ratio control member structured to move due to driving of an electric actuator. A control method for the hybrid vehicle includes: measuring a state of charge of a battery connected to the motor generator; and in response to regenerative operation of the motor generator in a state that the state of charge of the battery is equal to or higher than a predetermined level, consuming generated electric power by driving the electric actuator of the variable compression ratio mechanism.