Patent · US Expired

Actuator

US4286657A · kind A · utility

2Cited by
3References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 26, 1979
Grant dateSep 1, 1981
Priority date
Expiry dateDec 26, 1999

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B23/042
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

There is disclosed an actuator and a kickover tool including an actuator in which force is applied through the actuator by hydraulic means in which force due to the pressure medium in which the tool is submerged is substantially balanced across the seals of the pressure chambers and in which the force acting on the tool due to the pressure of the medium in which the tool is submerged remains balanced in the event any one of the seals becomes ineffective.

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