| 摘要 |
PROBLEM TO BE SOLVED: To provide a variable valve timing device of an internal combustion engine capable of mechanically locking a rotor 22 in the most retard angle position and the most advance angle position, respectively, with a simple constitution. SOLUTION: A hydraulic variable valve timing device consists of a housing 21 and rotor 22 relatively turnable at a given angle, and is turned by supplying oil pressure to an advance angle side hydraulic chamber 37 and a retard angle side hydraulic chamber 38 on both sides of vanes 34a-34d. A lock mechanism 41 consists of a lock pin 43 sliding in a cylinder 42 passing through the rotor 22, and with one end engaged with a first engaging hole in the most retard angle position through the biasing force of a coil spring. At operation, while the lock pin 43 is biased to an opposite side by oil pressure of the advance angle side hydraulic chamber 37 to be disengaged from the first engaging hole, the other end thereof is engaged with a second engaging hole in the most advance angle position by the oil pressure. During the operation, the rotor 22 is mechanically held in the most advance angle position so that an energy loss due to oil pressure supply is reduced. COPYRIGHT: (C)2009,JPO&INPIT
|
