Patent ID: 7512372

Claim:
A temperature-changing pressure roller assembly for use in a heated fuser roller and pressure roller type fusing apparatus to form a fusing nip with the heated fuser roller, the temperature-changing pressure roller assembly comprising: (a) a rotatable pressure roller including a cylindrical sleeve having an outer surface for forming the fusing nip with the heated fuser roller, and an inner surface defining a hollow interior to said rotatable pressure roller, said hollow interior having a first end and a second and opposite end; (b) a vortex tube assembly for simultaneously producing a hot air stream and a cold air stream, said vortex tube assembly being connected to said hollow interior of said rotatable pressure roll; and (c) control means connected to said vortex tube assembly for selectively controlling flow of said hot air stream and said cold air stream thereof through said hollow interior of said rotatable pressure roller, thereby selectively changing a temperature of said cylindrical sleeve of said pressure roller for preventing image over-fusing.