Patent · US Expired

Cardiac assist pump with steady rate supply of fluid lubricant

US4927407A · kind A · utility

422Cited by
21References
21Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 19, 1989
Grant dateMay 22, 1990
Priority date
Expiry dateJun 19, 2009

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61M60/148
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A centrifugal pump for left ventricle assist includes a pump housing forming an impeller chamber with inlet and outlet passages and enclosing an impeller rotatable to move blood through the impeller chamber, and a rotor chamber enclosing a rotor integral with the impeller and rotatable to drive the impeller. An elastically deformable seal member separates the rotor and impeller chambers, and includes an annular lip seal surrounding a shaft which joins the impeller and rotor. A saline solution is supplied at a constant fluid flow rate to the rotor chamber through an inlet passage, and leaves the rotor chamber by perfusing into the impeller chamber along the interface between the shaft and lip seal. The saline solution thus provides hydrodynamic bearings between the rotating shaft and rotor, and the fixed pump housing and lip seal, and further prevents blood in the impeller chamber from entering the rotor chamber. The lip seal is configured to encourage flow of saline solution along the lip seal/impeller shaft interface, while resisting the flow of blood along the interface.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.