Patent ID: 7854583

Claim:
A compressor comprising: a casing having at least one slot, the slot having a pair of side edges; a plurality of vane units disposed in said slot, each vane unit having a base and at least one airfoil projecting from the base, the base having a pair of mounting edges that are opposite each other and face said side edges, respectively, and a pair of engaging edges for engaging adjacent bases of adjacent vane units, a first groove extending along a first mounting edge of the base generally in parallel to a top surface of the base and aligned with a corresponding first groove of an adjacent vane unit base; and an elongated strip disposed in said first groove and having a length greater than a length of said mounting edge so as to be disposed in and extend along the first grooves of at least two adjacent vane units, wherein an air extraction cavity is defined in said casing between said base and a bottom of said slot and wherein a hole is defined to said base for drawing air into said air extraction cavity.