Phase control device and phase control method for variable valve timing device

Abstract

The invention relates to a phase control device and a phase control method for a variable valve timing device. The phase control device for the variable valve timing device can limit a lead-angle and a lag-angle of a camshaft phase angle that cannot be calculated accurately for the moment in a low-rotating speed area where the rotation fluctuation of an internal combustion engine is greater and the internal combustion engine rotates reversely and calculate the lead-angle and the lag-angle accurately under the condition that a cam is fixed to the lead-angle side on the intake side and the cam is fixed to the lag-angle side on the exhaust side. The device calculates the camshaft phase angle used for control of a valve timing change mechanism according to the detected crank angle position and cam angle position and updates the limit for the calculated camshaft phase angle under the condition that the calculated phase angle is on the lead-angle side on the intake valve side and that the camshaft phase angle is on the lag-angle side on the exhaust valve side according to the rotating speed of the internal combustion engine.

Description

technical field [0001] The present invention relates to a phase control device of a valve timing adjustment device, which is used to adjust the opening and closing timing of one or both of an intake valve and an exhaust valve according to the operating conditions of an engine. Background technique [0002] In recent years, in internal combustion engines mounted on vehicles, for the purpose of improving fuel consumption and reducing exhaust emissions, etc., variable valve timing devices in which the valve timings of intake valves and exhaust valves are variable are generally used. At present, most of the variable valve timing devices change the valve timing of the intake valve and exhaust valve driven by the camshaft by changing the camshaft phase angle (rotational phase of the camshaft relative to the crankshaft). [0003] In order to change the valve timing, it is necessary to detect the camshaft phase angle (rotational phase of the camshaft relative to the crankshaft). As ...

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Problems solved by technology

[0010] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a phase control device of a variable valve timing device, etc., which has a large fluctuation in the rotation of the internal combustion engine and a low rate of reverse rotation of the internal combustion engine. In the speed range, the advance angle and retard angle of the camshaft phase angle that cannot be calculated correctly for the time being are limited. In addition, if it is the intake side, the cam is fixed at the advance angle side, and if it is the exhaust side, the cam is fixed at the retardation angle. In the case of the angle side, the advance angle amount and the retard angle amount can be calculated correctly

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