US Patent 7121816 Scroll fluid machine

A scroll fluid machine has a fixed scroll in a housing and an orbiting scroll rotatably mounted to a driving shaft. A fixed wrap of the fixed scroll is engaged with an orbiting wrap of the orbiting scroll. The orbiting scroll is revolved at a certain eccentricity by the driving shaft, so that a gas sucked through the circumference of the housing is compressed as it moves toward the center, and discharged through the center. A gas-guiding bore is formed near the center of the orbiting scroll, and a heat-releasing rod is inserted in the bore. One end of the heat-releasing rod is projected from the fixed scroll to release heat to atmosphere.