Scroll-type refrigerant fluid compressor having a lubrication path through the orbiting scroll

A scroll-type refrigerant fluid compressor comprising:

• a housing;
• a fixed scroll fixedly disposed within said housing and having a first circular end plate from which a first spiral wrap extends;
• an orbiting scroll having a second circular end plate from which a second spiral wrap extends, said first and second spiral wraps interfitting at an angular and radial offset to form a plurality of line contacts defining at least one pair of sealed-off fluid pockets;
• a plate member having a spiral configuration disposed on a first axial end surface of said second circular end plate of said orbiting scroll engaging with said second spiral element of said orbiting scroll, so that direct contact between said first axial end surface of said second circular end plate of said orbiting scroll and an axial end surface of said first spiral wrap of said fixed scroll is prevented;
• a drive shaft rotatably supported by said housing;
• a rotation preventing means for preventing the rotation of said orbiting scroll during orbital motion;
• and
• a coupling means for operatively coupling an inner end of said drive shaft to said orbiting scroll, such that said orbiting scroll orbits to thereby change the volume of said at least one pair of sealed-off fluid pockets;
• said coupling means including an annular boss extending from a central portion of a second axial end surface of said second circular end plate of said orbiting scroll opposite to said first axial end surface, and a bushing operatively connected to said inner end of said drive shaft and rotatably disposed within said boss;
• wherein a hole having a first end and a second end opposite to said first end is axially formed through said second circular end plate of said orbiting scroll,
• wherein said first end of said hole is open to said second axial end surface of said second circular end plate of said orbiting scroll at a position within said annular boss, said second end of said hole is open to a central portion of said first axial end surface of said second circular end plate of said orbiting scroll, and wherein said plate member overlies said second end of said hole, and a restricted flow path is formed between said plate member and said first axial end surface.