Hermetic scroll compressor with welded casing section

Claim 1

A hermetic scroll compressor comprising a hermetic casing, a scroll compressor section and an electric motor section both contained in said hermetic casing, said scroll compressor and motor sections being connected with each other through a rotary shaft supported by a frame, a space in said hermetic casing being separated into upper and lower chambers by said frame, said compressor section including stationary and orbiting scroll members each having a disk-shaped end plate and a spiral wrap protruding upright therefrom and assembled together with their wraps meshing inwardly with each other to define compression chambers therebetween, said orbiting scroll member being operably engaged by an eccentric shaft portion formed on said rotary shaft and being provided with rotation prevention means, said stationary scroll member being formed in its end plate with a discharge port opening through a central portion of the end plate and a suction port opening through a peripheral portion thereof, said orbiting scroll member being driven in orbital motion relative to said stationary scroll member without rotation about its own axis to move said compression chambers toward center of both scroll members with capacity of said compression chambers progressively decreased so that a refrigerant gas drawn through said suction port into said compression chambers is compressed, discharged through said discharge port to said upper chamber and introduced therefrom through a communication passage formed in a peripheral portion of said frame to said lower chamber, in which said electric motor section is disposed, to be delivered to outside of said compressor through a discharge pipe, wherein said hermetic casing has an upper casing section, barrel section and a lower casing section which are formed separately and hermetrically welded together, said barrel section is formed with a sheet material rolled into a cylindrical shape and welded at opposite ends thereof to form a weld joint, and said frame is fixedly secured in said barrel section of said casing with said weld joint on said barrel section disposed within a circumferential width of said communication passage so that entire periphery of said frame except for the portion where said communication passage is formed is in close contact with an inner peripheral surface of said barrel section of said casing.