公开(公告)号：GB2138505A

公开(公告)日：1984-10-24

申请号：GB8311117

申请日：1983-04-23

Applicant: STEWART DUNCAN ROSS

Inventor： STEWART DUNCAN ROSS

IPC: F15B11/12 ,  F15B15/20

Abstract: A fluid-pressure-operated actuator is arranged to have three set positions and preferably a fail-safe characteristic in one of the three positions. In one embodiment an H-section piston moves in an actuator body and is set in its two extreme positions by fluid pressure introduced behind the web of the piston through one or other of spindles having heads and bores. To set the intermediate position, annular pistons can be moved along the spindles by pressure introduced at inlet pipes in the body until those pistons contact the heads of the spindles. The spindles are adjustable in the body to set the intermediate position of the piston and adjusting bolts set the extreme positions of the piston. For a fail-safe situation, a reservoir and control valve are introduced. As an alternative to annular pistons springs acting through top-hat shaped buffers can be used giving a fail-safe situation in the intermediate position of the piston.

公开(公告)号：GB2138505B

公开(公告)日：1986-09-10

申请号：GB8311117

申请日：1983-04-23

Applicant: STEWART DUNCAN ROSS

Inventor： STEWART DUNCAN ROSS

IPC: F15B11/12 ,  F15B15/20

Abstract: A fluid-pressure-operated actuator is arranged to have three set positions and preferably a fail-safe characteristic in one of the three positions. In one embodiment an H-section piston moves in an actuator body and is set in its two extreme positions by fluid pressure introduced behind the web of the piston through one or other of spindles having heads and bores. To set the intermediate position, annular pistons can be moved along the spindles by pressure introduced at inlet pipes in the body until those pistons contact the heads of the spindles. The spindles are adjustable in the body to set the intermediate position of the piston and adjusting bolts set the extreme positions of the piston. For a fail-safe situation, a reservoir and control valve are introduced. As an alternative to annular pistons springs acting through top-hat shaped buffers can be used giving a fail-safe situation in the intermediate position of the piston.