Patent ID: 6024061
Filing Date: 2000-02-15
Classification: F01L,Y10T

Abstract:
A vane-type hydraulically adjustable phase rotational drive apparatus having at least one accommodating chamber defined between two relatively rotatable members, one of said rotatable members comprising a housing and the other of said rotatable members comprising a rotor, intermeshed projections of said two relatively rotatable members including a vane member of said rotor cooperatively defining a leading fluid chamber and a lagging fluid chamber within said accommodating chamber, a volume of each of which is variable in accordance with a rotational position of said rotor with respect to said housing, a relative imbalance between the magnitudes of fluid volumes supplied to said leading and lagging chambers causing corresponding relative rotary forces between said relatively rotatable members, said apparatus further comprising:a fluid supply controller means for selectively adjusting a first fluid supply to press said vane member toward a first of two circumferential ends of said accommodation chamber, and for selectively adjusting a second fluid supply to press the vane member toward a second of said two circumferential ends of the accommodation chamber;said controller means having a first, end holding mode in which the vane member is held at the first end of the accommodation chamber and a second mode in which the vane member is rotated toward the second end of the accommodation chamber;a fluid pressure of said second fluid supply in the end holding mode being lower than a fluid pressure of said second fluid supply in the second mode, said fluid pressure of said second fluid supply in the end holding mode being higher than a fluid pressure of said first fluid supply in the end holding mode; anda motion restraining means having a first restrained state for preventing relative motion between said relatively rotatable members and a second un-restrained state for permitting relative motion between said relatively rotatable members;wherein the restrained state is removed by a fluid force, including at least the second fluid supply pressure in the end holding mode, that opposes a force generated by a bias member of said restraining means.