| 摘要 |
A three-position booster valve mechanism comprises an operating member (25) for moving a supply and exhaust valve (8, 10). A piston-cylinder control system (20) is provided for moving the operating member between a first position in which the supply and exhaust valve are closed, a second position in which the supply valve is open and the exhaust valve is closed, and a third position in which the supply valve is closed and the exhaust valve is open. A pilot port (24) is provided for moving the operating member in between the first, second and third positions in dependence of a pilot pressure. According to the invention the piston-cylinder control system connects to the operating member at a central point of application CPA in between the supply and exhaust valve. The operating member extends in opposing directions from said central point of application towards the supply and exhaust valve. |
