US Patent 9163524 Variable geometry turbine seal

According to an aspect of the invention, there is provided a variable geometry turbine comprising: a turbine wheel mounted for rotation about a turbine axis within a housing, the housing defining an annular inlet surrounding the turbine wheel and defined between first and second inlet sidewalls; and a cylindrical sleeve axially movable across the annular inlet to vary the size of a gas flow path through the annular inlet, the annular inlet being divided into at least two axially offset inlet portions; and a ring-like seal adjacent a free end of the sleeve, at least a part of the ring-like seal being located in-between the sleeve and the inlet portions, or a structure defining the inlet portions.