Scroll type fluid displacement apparatus with pressure communicating passage between pockets

A scroll type fluid displacement apparatus comprising:

• a housing;
• a fixed scroll member fixedly disposed relative to said housing and having a first end plate from which a first wrap extends into the interior of said housing;
• an orbiting scroll member having a second end plate from which a second wrap extends, and said first and second wraps interfitting at an angular and radial offset to make a plurality of line contacts to define at least one pair of sealed off fluid pockets;
• a driving mechanism including a drive shaft rotatably supported by said housing and connected to said orbiting scroll member to effect orbital motion of said orbiting scroll member by the rotation of said drive shaft;
• rotation preventing means connected to said orbiting scroll member for preventing the rotation of said orbiting scroll member during the orbital motion of said orbiting scroll member;
• and
• equalizing means for minimizing fluid pressure difference between said pair of fluid pockets and thereby reducing vibration in this apparatus, said equalizing means including two holes formed in said first end plate and fluid passage means for placing said two holes in continuous fluid communication with one another, said holes being located at symmetrical positions for said second wrap to simultaneously cross over the two holes.

A scroll type fluid displacement apparatus comprising:

• a housing;
• a fixed scroll member fixedly disposed relative to said housing and having a first end plate from which a first wrap extends into the interior of said housing;
• an orbiting scroll member having a second end plate from which a second wrap extends, and said first and second wraps interfitting at an angular and radial offset to make a plurality of line contacts to define at least one pair of sealed off fluid pockets;
• a driving mechanism including a drive shaft rotatably supported by said housing and connected to said orbiting scroll member to effect orbital motion of said orbiting scroll member by the rotation of said drive shaft;
• rotation preventing means connected to said orbiting scroll member for preventing the rotation of said orbiting scroll member during the orbital motion of said orbiting scroll member;
• and
• equalizing means for minimizing fluid pressure difference between said pair of fluid pockets and thereby reducing vibration in the apparatus, said equalizing means including two holes formed in said first end plate and fluid passage means for placing said two holes in continuous fluid communication with one another, said holes being located at symmetrical positions for said second wrap to simultaneously cross over the two holes and in the area where said fluid pockets are initially formed so that the pair of fluid pockets are placed in fluid communication with one another when said fluid pockets are initally formed.