Patent · US Expired

Hydraulic cylinder locking device

US4524676A · kind A · utility

20Cited by
6References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 19, 1984
Grant dateJun 25, 1985
Priority date
Expiry dateJan 19, 2004

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF15B15/261
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A hydraulic cylinder having a locking device disposed in either, or both head ends which attach to the cylinder, has a piston reciprocally movable within a piston chamber formed in the cylinder. A stud member having a groove portion and a stud portion, secures to the piston for reciprocal movement therewith. The stud member axially moves within a stud bore formed in the head end such that, the stud bore acts as a variable volume stud chamber. A plunger member, disposed in the head end, is in fluid communication with the variable volume stud bore such that, movement of the stud member into the stud bore increases the fluid pressure, thus forcing the plunger out of contact with the stud portion of the stud member. When a predetermined pressure occurs, an outlet valve to the stud bore opens, reducing the fluid pressure and allowing the plunger to be urged into engagement with the groove portion of the stud member thus effecting a locked condition. An inlet valve to the stud bore allows introduction of additional fluid pressure to the stud bore sufficient to force the plunger out of engagement with the groove portion of the stud member, thus effecting an unlock of the cylinder. A commo…

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