Patent ID: 6655930
Filing Date: 2003-12-02
Classification: F04D,Y10S

Abstract:
A centrifugal pump, for pumping a low temperature fluid, comprising:a pump portion; a motor portion on said pump portion; said pump portion comprising an impeller having a first rotation axis; said motor portion comprising a motor having a second rotation axis; said first rotation axis being coaxial with said second rotation axis; said motor being connected for driving said impeller during operation of said centrifugal pump to drive said pump portion and pump said low temperature fluid; an insulating jacket means for thermally insulating at least said motor portion; said insulating jacket means surrounding at least said motor portion; at least a first vacuum jacket in said insulating jacket means; said first vacuum jacket comprising at least a low pressure vacuum between a motor outer surface and an inner surface of said first vacuum jacket, whereby tight contact between said insulating jacket means and said motor portion and said coaxial alignment provides increased thermal efficiency, reduced size, and simplified construction; a pot; said pot being sealed around a lower portion of said pump portion; said pot solely receiving said low temperature fluid during said operation; an intake pipe in said lower portion extending away from said pump portion along said first rotation axis into said pot; said intake pipe and said impeller being in fluid communication; and said intake pipe and said impeller transporting said low temperature fluid from said pot during said operation, thereby restricting direct contact of said low temperature fluid to said pump portion and providing a reduced pump surface area with an improved startability.