VALVE GEAR DRIVE DEVICE FOR INTERNAL COMBUSTION ENGINE

PROBLEM TO BE SOLVED: To prevent breakage of an internal combustion engine even if abnormality occurs in a second operation valve in a valve gear drive device and to continue at least necessary minimum operation by establishing normal engine cycle. SOLUTION: This device includes: a control chamber 18 connected to a high pressure chamber 2 in which pressurized working fluid is stored, a first operation valve 20 provided between the control chamber 18 and the high pressure chamber 2 and opened when a valve 11 is opened for introducing working fluid to the control chamber 18 from the high pressure chamber 2, and a second operation valve 30 provided in a discharge passage 19 connected to the control chamber 18 and opened when the valve 11 is closed for discharging working fluid from the control chamber 18. A release passage 45 is connected to the control chamber 18 and a rupture disk 46 bursting at a prescribed pressure is provided in the release passage 45. Burst part opening area of the rupture disk 46 in such a state that the second operation valve 30 is closed is set to an area with which the valve 11 can be opened and closed as well after the burst of the rupture disk 46. COPYRIGHT: (C)2010,JPO&INPIT