Valve timing changing device

Abstract

The invention provides a valve timing changing device, by which a vane rotor is kept at a central position when the engine is started to prevent sloshing, knocking noise and wearing. The device includes a housing rotor (30), a vane rotor (2), an advance angle passageway (13) communicated with an advance angle chamber for operating oil to pass through, a lag angle passageway (14) communicated with a lag angle chamber for the operating oil to pass through, and a lock mechanism (40) which locks the vane rotor at a center position relative to the housing rotor and unlocks the lock by means of the hydraulic pressure of the operating oil. The lock mechanism includes an advance angle lock bar (42) and a lag angle lock bar (44). The advance angle passageway (13) guides the hydraulic pressure to unlock the lock of the advance angle lock bar and the lag angle lock bar, and the lag angle passageway (14) guides the hydraulic pressure to maintain the unlocking of the lock of the lag angle lock bar. The vane rotor is kept at the central position when the engine is started so as to ensure the stable starting performance of the engine.

Description

technical field [0001] The present invention relates to a valve timing changing device for changing the opening and closing timing (distribution timing) of an intake valve or an exhaust valve of an internal combustion engine according to operating conditions. Background technique [0002] It is known that a conventional valve timing changing device includes the following components, etc.: a casing rotor (casing, external rotor, etc.) that rotates synchronously with the crankshaft; The vane rotor rotates synchronously with the camshaft and is housed in the housing rotor, the housing chamber of the vane rotor is divided into two parts, a retarded angle chamber and an advanced angle chamber, and the vane rotor can be moved relative to the housing. The rotor rotates relatively in a predetermined angle range (between the most advanced angle position and the most retarded angle position); the locking mechanism (locking pin and spring, locking body and spring, etc.) locking the va...

AI Technical Summary

Problems solved by technology

[0007] In this way, in the case of directly using the working oil in the advanced angle chamber and the retarded angle chamber, it is easy to be affected by the hydraulic pressure of the working oil in the advanced angle chamber and the retarded angle chamber, and there is a possibility that the lock of the locking mechanism is accidentally released or the lock cannot work normally. Possibility, on the other hand, in the case of setting a dedicated oil passage, the structure becomes complicated, resulting in an increase in cost due to processing costs or increased parts

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