Scroll compressor having relief ports to open first and second compression chambers

A scroll compressor comprising:

• a compression mechanism including
• a fixed scroll having an end plate and a first scroll wrap,
• an orbiting scroll having a second scroll wrap, the orbiting scroll being eccentrically rotatable relative to the fixed scroll,
• a first compression chamber facing an outer peripheral surface of the second scroll wrap of the orbiting scroll and a second compression chamber facing an inner peripheral surface of the second scroll wrap of the orbiting scroll being formed by allowing the first scroll wrap of the fixed scroll to mesh with the second scroll wrap of the orbiting scroll,
• the end plate of the fixed scroll having
• a discharge port formed in a middle part of the end plate to discharge fluid compressed in the compression chambers to a discharge space,
• a plurality of relief ports formed outside the discharge port and each having one end open to the associated first or second compression chamber and the other end connected with the discharge space, and
• relief valves being configured to open and to close an associated relief port of the plurality of relief ports, and
• the plurality of relief ports having
• a first relief port configured to open only to the first compression chamber of both the compression chambers,
• a second relief port configured to open only to the second compression chamber of both the compression chambers, and
• a third relief port configured to open to the first compression chamber and the second compression chamber alternately due to eccentric rotation of the orbiting scroll,
• the first relief port being disposed near an inner peripheral surface of the first scroll wrap of the fixed scroll, the second relief port being disposed near an outer peripheral surface of the first scroll wrap of the fixed scroll, and the third relief port being disposed to open midway between the inner and outer peripheral surfaces of the scroll wrap of the fixed scroll.