Patent ID: 7695259

Claim:
A rotary fluid pressure device of the type having a housing means defining a fluid inlet and a fluid outlet, a fluid energy-translating displacement means including a first member and a second member, operably associated with said first member; said first member and said second member having relative movement, and interengaging to define a plurality N of expanding and contracting fluid volume chambers in response to said relative movement; a valve member providing fluid communication between said fluid inlet and said expanding volume chambers, and between said fluid outlet and said contracting volume chambers; a plate member defining a plurality N of upstream fluid passages in commutating fluid communication with said valve member and a plurality N of downstream fluid passages, with each said downstream fluid passage being in open fluid communication with one of said plurality of volume chambers; a plurality M of upstream fluid passages being in direct, relatively unrestricted, continuous fluid communication with a plurality M of downstream fluid passages; characterized by: (a) a plate assembly including said plate member and at least one assembly selected from the group consisting of a cover plate assembly and a control valve assembly; (b) said plate member including a plurality M of upstream manifold passages, with each of said plurality of upstream manifold passages being in open fluid communication with one of a plurality M of upstream fluid passages and having an opening in an exterior surface of said plate member, and a plurality M of downstream manifold passages, with each of said plurality of downstream manifold passages being in fluid communication with one of a plurality M of downstream fluid passages and having an opening in said exterior surface of said plate member; wherein: (i) said cover plate assembly defining a mounting surface being in sealing engagement with said exterior surface of said plate member with said cover plate assembly providing unrestricted fluid communication between at least one of said plurality of upstream manifold passages and at least one of said plurality of downstream manifold passages in said plate member; and (ii) said control valve assembly defining a mounting surface being in sealing engagement with said exterior surface of said plate member with said control valve assembly being operable in a first position to provide relatively unrestricted fluid communication between at least one of said plurality of upstream manifold passages and at least one of said plurality of downstream manifold passages in said plate member, and operable in a second position to block fluid communication between at least one of said plurality of upstream manifold passages and at least one of said plurality of downstream manifold passages in said plate member.