Patent ID: 7520735

Claim:
A submersible pump comprising: a motor containing a motor fluid; a pump above said motor; a seal section between said motor and said pump, said seal section defining a bellows chamber having a first end and a second end; a shaft that communicates said motor with said pump, said shaft running through said bellows chamber in said seal section; a communication tube in said bellows chamber surrounding said shaft, defining an annular passageway in fluid communication with the motor fluid; a bellows in said bellows chamber and surrounding said communication tube, said bellows comprised of a first collapsible section and a second collapsible section said communication tube having an aperture for flowing said motor fluid from the passageway into an interior of said bellows; said first collapsible section having a first end secured at said first end of said bellows chamber, said first collapsible section having a first cross-sectional area; said second collapsible section having a second end secured at said second end of said bellows chamber, said second collapsible section having a second cross-sectional area larger than said first cross-sectional area; a coupling member having an outside portion joined to a first end of said second collapsible section, an inside portion joined to a second end of said first collapsible section, and a transitional portion therebetween, said inside portion and said transitional portion being located within said second collapsible section, said coupling member surrounding said communication tube; wherein said bellows has a fully expanded position wherein said second collapsible section is collapsed fully within said transitional portion of the coupling member, and said second collapsible section is fully extended with the outside portion of the coupling member bearing against a stop surface on the first end of the bellows chamber.