VARIABLE VALVE DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

Provided is a variable valve device for an internal combustion engine, capable of improving engine characteristics by increasing the maximum valve lift of an intake valve to a large valve lift while preventing excessive lost motion operation of lost motion mechanisms. The variable valve device includes intake- and exhaust-side swing arms that pivot to open and close intake valves (3a, 3b) and exhaust valves (61a, 61b) in two cylinders #1, #2, intake- and exhaust-side hydraulic lash adjusters (10a, 10b, 65a, 65b) that serve as pivot points of the respective swing arms, a variable valve system that continuously varies valve lift characteristics of the intake valves and lost motion mechanisms (11) that stop opening and closing of the intake exhaust valves by lost motion of the intake- and exhaust-side hydraulic lash adjusters on the cylinder #1. The maximum valve lifts of the intake valves are set larger than valve lifts of the exhaust valves. The minimum valve lifts of the intake valves are set smaller than the valve lifts of the exhaust valves.

主权项

1. A variable valve device for an internal combustion engine, comprising:
intake and exhaust valves biased in respective valve close directions by spring forces of valve springs; a pair of intake- and exhaust-side swing arms that pivot to open and close the intake and exhaust valves, respectively; a pair of pivot members that serve as pivot points of the swing arms; a variable valve system that continuously varies a valve lift characteristic of the intake valve; a valve drive system that causes the exhaust-side swing arm to drive the exhaust valve at a constant valve lift; and lost motion mechanisms that stop opening and closing of the intake and exhaust valves by lost motion of the pivot members, wherein a maximum valve lift of the intake valve is set larger than the valve lift of the exhaust valve; and wherein a minimum valve lift of the intake valve is set smaller than the valve lift of the exhaust valve.