Scroll type compressor having a ring for compressive force transmission and orbit determination

A scroll type compressor having a movable scroll eccentrically orbitable about a drive shaft in a housing for defining a compression chamber in cooperation with a fixed scroll disposed opposite the movable scroll, said compression chamber decreasing in size in accordance with the orbital movement of said movable scroll for compressing gas in the compression chamber, said housing and said movable scroll being made of aluminum, and said compressor further comprising:

• a first ring orbitable with the movable scroll between the movable scroll and the housing for receiving compressive reaction force acting on the movable scroll parallel to the axis of the drive shaft;
• a second ring engaged with the housing for receiving the compressive reaction force received by and acting on said first ring, said second ring being made of an iron-base metal;
• a plurality of load bearing members disposed about said first ring for transferring the compressive reaction force from the movable scroll to the second ring;
• a plurality of projections and corresponding recesses provided, respectively, on said second ring and said housing with said projections inserted in the corresponding recesses to prevent said second ring from rotating relative to said housing;
• a plurality of cylindrical elements disposed about said first ring for preventing the movable scroll from rotating about its axis;
• and
• a plurality of cylindrical pockets in both said movable scroll and said second ring into which are slidably disposed said cylindrical elements, each pocket having a larger diameter than each cylindrical element for permitting the orbital movement of the movable scroll, each pocket having a bottom at a sufficient depth to avoid contact between the associated cylindrical element and the bottom of the pocket.