Abstract: A scroll-type fluid machine includes an orbiting scroll member and a stationary scroll member each of which has an end plate and a spiral wrap protruding upright therefrom. The scroll members are assembled together such that their wraps mesh with each other. Closed spaces are defined by the wraps and end plates of both scroll members, and are progressively moved towards the center of the scroll members while decreasing their volumes in accordance with an orbiting movement of the orbiting scroll member. The edges of the projecting end of the wrap of each scroll member are chamfered. Also, steps are formed in conformity with the configuration of each spiral wrap on respective corners of the groove bottom between adjacent turns of the wrap. The chamfered edges of the projecting end of the wrap of each scroll member faces the steps on the groove bottom of the opposing scroll member, respectively, when the scroll members are assembled together.

Abstract: A method and an apparatus for automatically positioning stationary and orbiting scroll members of a scroll-type fluid machine.

Abstract: A method of processing a scroll member having a spiral wrap and an end plate which is conducted by effecting a shaving on at least one side surface of the spiral wrap by a tool while applying to the tool both of an axial small force and an ultrasonic oscillation simultaneously. An apparatus is proposed which comprises a shaving tool having a spiral groove of the same configuration as the spiral wrap, and a cutting edge portion formed on at least one side edge of the groove over the entire length of the side edge. A tool supporting device supports the shaving tool, and a blank supporting device supports a scroll blank such that the scroll blank opposes to the shaving tool. A device is connected to the tool supporting means and is adapted to impart to the tool a pressing force necessary for effecting the shaving, and an ultrasonic oscillation generating device is adapted to impart an ultrasonic oscillation to one of the tool or the blank.

Abstract: An improved method of producing a scroll type compressor having an orbital scroll member and a stationary scroll member. The orbital scroll member is fabricated by a process comprising the steps of: forming an end plate and a spiral wrap separately, the end plate being composed of an upper half part having a discontinuous joining portion for joining the spiral wrap and a lower half part having an oil passage. The upper half part and the lower half part of the end plate are fixed to each other through mutual engagement between locating projections formed by a plastic work on one of the half parts and mating holes formed in the other of the half parts.