The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 2000
Filed:
Oct. 15, 1997
Applicant:
Inventors:
Assignee:
Roper Holdings, Inc., Wilmington, DE (US);
Primary Examiner:
Int. Cl.
CPC ...
F04D / ; F04D / ;
U.S. Cl.
CPC ...
415111 ; 415116 ; 261 341 ; 261D / ;
Abstract
A centrifugal pump having a rotatable impeller that operates to drain liquid into the intake of the pump. An air-introduction passage connects with a subatmospheric pressure region at the back of the impeller. Air introduced through this passage is mixed with a portion of the fluid pumped, and the air-fluid mixture is expelled as the discharge of the pump.