Seal grid assembly for rotary piston mechanism

摘要

The improved seal grid assembly is for a rotary compressor or expansion engine of the type having a rotor supported for planetation in a multi-lobe housing cavity and comprises, in combination with a non-rotating seal at the juncture of the housing lobes, a sealing means including a sealing surface movable between a retracted position where it is out of engagement with the peripheral wall and an extended position where it is in engagement with the peripheral wall of the housing cavity. A vent passage means is also provided in the rotor to communicate a space defined between the sealing means and rotor with the working chambers to conduct gaseous fluid which pressurizes said space so as to provide movement of the sealing surface of the associated seal means to the retracted position just prior to engagement with the non-rotating seal and to the extended position after such engagement with the non-rotating seals at each of the housing lobe junctures.