Patent · US Expired

Pressure equalizing device and deep well motor/pump combination

US4425087A · kind A · utility

10Cited by
6References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 27, 1981
Grant dateJan 10, 1984
Priority date
Expiry dateNov 27, 2001

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16J15/164
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

In a fluid-filled electric motor having a throughgoing shaft the requirements (i) internal fluid pressure maintained above ambient during installation (ii) equalization of internal and ambient pressures at run-up (iii) no solid particles contaminate internal fluid are met by a pressurizing apparatus in which internal motor pressure above ambient moves a piston against a spring. The pressure ensures integrity of a seal and pressure and temperature variations are accommodated by piston movement. The seal runs clear of the motor shaft allowing equalization of internal and ambient pressures during run up to speed. Only liquid can enter the spring chamber.

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