Rotary compressor with labyrinth sealing

Claim 1

A rotary mechanism such as a compressor, expansion engine or the like comprising: a. an outer body comprising a pair of axially-spaced end walls and an intermediate wall defining a cavity therebetween; b. an inner body mounted for relative rotation within said cavity and having its axis eccentric to the axis of said outer body, the peripheral surface of said inner body having a plurality of nose portions and being substantially a hypotrochoid and the inner peripheral surface of said outer body intermediate wall being substantially the outer envelope of the peripheral surface of the inner body such that a plurality of fluid working chambers are formed between said inner body and said intermediate wall peripheral surface; c. at least one radially-movable seal strip carried by said intermediate wall and disposed parallel to the axis of said mechanism at a position such that the inner edge of said strip substantially generates the hypotrochoidal peripheral surface of the inner body during relative rotation of said bodies and means for urging said seal strip radially inwardly into sealing engagement with said hypotrochoidal peripheral surface; d. said outer body having intake and outlet ports for communication with said working chambers and disposed on opposite sides of said seal strip; and e. at least one of said peripheral surfaces having labyrinth-type recesses over at least a portion of said surfaces to provide sealing cooperation between the nose portions of the inner body and said intermediate wall peripheral surface.