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(11) | EP 2 474 713 A8 |
(12) | CORRECTED EUROPEAN PATENT APPLICATION |
published in accordance with Art. 153(4) EPC |
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(54) | CONTROL DEVICE FOR OIL PRESSURE VALVE VARIABLE TIMING MECHANISM |
(57) In a hydraulic variable valve timing mechanism comprising a lock pin that locks a
vane rotor and a housing against relative rotation in the most retarding phase, a
specified angle α is set so that release of the lock pin is started at a time when
positive cam torque acts on the vane rotor. When the crank angle reaches the specified
angle α1 supply of hydraulic pressure to the advancing oil chamber is started to release the
lock pin from the engagement with the lock hole, thereby enabling a reliable release
of the lock pin prior to start of change of valve timing.
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