US Patent 7293969 Tip seal in a scroll fluid machine

A scroll fluid machine comprises a stationary scroll having a stationary wrap and an orbiting scroll having an orbiting wrap. A tip seal is provided in a tip-seal groove at the ends of the stationary and orbiting wraps to allow the stationary wrap to engage with the orbiting wrap slidably. The tip seal comprises a sealing material in the tip-seal groove and a backup material between the sealing material and the bottom of the tip-seal groove. The tip seal tightly contact the backup material without an adhesive to keep their sideward positional relationship exact.