Patent ID: 6716009
Filing Date: 2004-04-06
Classification: F04C

Abstract:
A scroll type compressor comprising:a housing having a fixed scroll member which has a fixed base plate and a fixed spiral wall that extends from the fixed base plate; a movable scroll member placed in the housing, the movable scroll member having a movable base plate and a movable spiral wall that extends from the movable base plate, the movable spiral wall being engaged with the fixed spiral wall; a plurality of compression chambers defined between the movable scroll member and the fixed scroll member, the compression chambers being moved radially and inwardly to compress gas by orbiting the movable scroll member relative to the fixed scroll member while reducing their volume, the compression chambers having at least a first intermediate compression chamber and a second intermediate compression chamber, in which gas compression is in progress, respectively; a discharge port formed substantially at the center of the fixed base plate or the movable base plate for sending the compressed gas to an outside of the housing; a communication passage for interconnecting each intermediate compression chamber with the discharge port, the communication passage having at least a first portion and a second portion, the first portion extending from the first intermediate compression chamber, the second portion extending from the second intermediate compression chamber, the first portion and the second portion meeting at a meeting point on the way in the communication passage before reaching the discharge port; and a relief valve placed between the meeting point and the discharge port inclusive of the meeting point in the communication passage, wherein the relief valve opens the communication passage when the pressure in the first and the second intermediate pressure chambers is higher than the pressure in the discharge port.