Loading patent…
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsKoji Wada, Tatsuhiko Takahashi
Estimating the term…
Valve timing control apparatus for engine includes a cam phase actuator (1113) composed of a first rotor (1) rotatable with a crank shaft, a second rotor (6) mounted on a cam shaft (7) and a lock mechanism (15, 16, 18) for locking the second rotor to the first rotor, a pump (1118) for generating a hydraulic pressure, an ECU for computing a current value corresponding to a pressure for clearing a locked state at the first relative angle for shifting the first relative angle to a second angle, and an OCV (1114) for supplying a pressure for regulating a cam phase of the second rotor in dependence on the current value. The ECU computes a first current value for generating a first pressure for releasing the locked state. The first current value is supplied to the OCV for a predetermined time before shifting the first relative angle.
A valve timing control apparatus for an internal combustion engine, comprising:
Dependencies are inferred from the claim text.
From the US filing history. Foreign family members aren’t listed.
Backward citations are indexed for grants only.
Variable control of the intake valves only: changing the valve timing only
Valve-gear or valve arrangements, e.g. lift-valve gear: characterised by the provision of means for changing the timing of the valves without…
During engine operation: fully variable control of valve lift and timing using camless actuation systems such as hydraulic, pneumatic or…
Characterised by what is learned or calibrated: characteristics of actuators
Term end not estimated
1. Field of the Invention
The present invention relates generally to a valve timing control apparatus for controlling valve open/close timing (hereinafter referred to simply as the valve timing) at which an intake valve or an exhaust valve of an internal combustion engine is opened and/or closed in dependence on operating state or condition of the engine.
2. Description of Related Art
In the course of the description which follows, reference is made to the drawings, in which:
FIG. 1 is a characteristic diagram for graphically illustrating a relation between an electric current supplied to an oil control valve and a hydraulic pressure prevailing downstream of the oil control valve;
FIG. 2 is a characteristic diagram for graphically illustrating a relation between the oil control valve current and a hydraulic pressure supplied to a valve timing advancing hydraulic chamber;
The present invention will be described in detail in conjunction with what is presently considered as preferred or typical embodiments thereof by reference to the drawings. In the following description, like reference characters designate like or corresponding parts throughout the several views.
Now, the valve timing control apparatus according to a first embodiment of the present invention will be described in detail by reference to the drawings. Incidentally, the mechanical structure of the valve timing control apparatus according to the instant embodiment of the invention is essentially same as that of the conventional apparatus described hereinbefore in conjunction with FIGS. 18 to 23. The valve timing control apparatus now under consideration differs from the conventional one only in several operations performed by the ECU 1117. Accordingly, the following description will primarily be directed to the operations or processings which differ from those of the conventional apparatus. With regard to the other respects, repeated description will be omitted.
In the description which follows, it is presumed that the relative angle (valve timing) of the cam shaft relative to the crank shaft is controlled, that the hydraulic passage arrangement as adopted is such that the lock pin 15 can be released or unlocked from the locked state under the hydraulic pressure which is effective for advancing the valve timing and that the retaining hole 18 for the lock pin 15 is located at the most retard position (i.e., the position at which the valve timing is most retarded).