Scroll-type fluid machine with grease-lubricated orbiting bearing

A scroll-type fluid machine comprising:

• a casing;
• a fixed scroll having a flange surface attached to the casing, and a wrap portion provided on a surface of an end plate;
• an orbiting scroll having a wrap portion provided on a surface of an end plate, and provided in an opposed relationship with the fixed scroll, and orbiting with respect to the casing;
• a back surface plate provided at a back surface of the end plate of the orbiting scroll,
• a drive shaft connected through a crank portion to the orbiting scroll and performing rotation-drive;
• a cooling fan supplying cooling air into an interior of the casing;
• a plurality of compression chambers which are defined between the wrap potion of the fixed scroll and the wrap portion of the orbiting scroll;
• and
• a conductive brush causing the orbiting scroll and the casing to be conducted by causing the back surface plate and the casing to be conducted.