| 摘要 |
Invention relates to a directional control valve (10) for fluid power system, comprising at least three operational positions (12) and in which a flow directing element arranged operable by control fluid so that applying of pressure of the control fluid (16) to the flow directing element causes the flow directing element to change its position, and spring unit (20) applying force to the flow directing element so that the force opposes the change of position. The spring unit (20) comprises a spring system (22, 24) which provides a discontinuously increasing change of the spring force exerted by the spring unit (20). |
