| 摘要 |
<p>It is the object of the present invention to provide a spring operated valve actuator with variable return force, utilizing a compact and space efficient spring system which can establish closing forces on a valve mechanism which are closely adapted to the closing characteristics needed for the valve. This is provided according to the invention by the use of a compact spring mechanism with a brief, but very powerful closing characteristic, and where the energy provided by the spring mechanism is distributed during the whole movement of the valve with varying forces localized according to needs. The essential novel and characteristic mechanical feature by this actuator means, which according to the invention is provided with a spring mechanism and a movable piston, is that the spring mechanism and the piston is mechanically, drivingly interconnected by the means of a variable gear mechanism (3, 4, 10).</p> |
