Patent ID: 7758326
Filing Date: 2010-07-20
Classification: F04C

Abstract:
1. A scroll fluid machine comprising an orbiting scroll and a fixed scroll equipped with wraps erected on end-plates, compression chambers defined with the orbiting scroll orbiting in a state of being inhibited from self-turning relative to the fixed scroll, and a back pressure chamber formed on a face of the orbiting scroll opposite from the wrap, the machine further having a back pressure port formed in an end-plate of the orbiting scroll and connecting from a compression chamber side opening opened on a compression chamber side to a back pressure chamber side opening opened on a back pressure chamber side, wherein the compression chamber side opening is opened and closed by the end-plate of the fixed scroll as connection and blockage of the back pressure port is performed according to orbiting motion of the orbiting scroll; wherein at a starting position of the orbiting scroll of 0° the compression chamber defined on an inner line side of the wrap of the orbiting scroll has finished suction; wherein when the orbiting scroll is between 270° position and 0° position the compression chamber side opening is opened to the compression chamber so that the compression chamber and the back pressure chamber can communicate with each other; when the orbiting scroll is between 90° position and 180° position the compression chamber side opening is closed to the compression chamber so that the compression chamber and the back pressure chamber are blocked from each other.