Apparatus for simultaneously adjusting fluid pressures in a dual fluid system and associated method

摘要

A method and apparatus for simultaneously adjusting the fluid pressures in a dual hydraulic circuit arrangement in which in a first hydraulic circuit pressurized fluid is supplied from a first pressure source to a first fluid pressure activated device and in a second hydraulic circuit pressurized fluid is supplied from a second pressure source to a second pressure activated device, comprising a cylinder having opposite closed ends and spaced bulkheads therein defining a central chamber between the bulkheads and a pair of chambers on respective opposite sides of the bulkheads. A pair of spaced first pistons are slidably mounted in the central chamber to define a control pressure chamber therebetween and first and second primary fluid pressure chambers between respective pistons and the bulkheads. The first primary fluid pressure chamber is connected to the first pressure source while the second primary fluid chamber is connected to the second pressure source. A pair of second pistons are secured for common movement with the first pistons and the second pistons are respectively mounted between the bulkheads and the closed ends of the cylinder to define first and second secondary fluid pressure chambers between the second pistons and respective bulkheads. The first and second secondary chambers are respectively connected to the first and second fluid pressure activated devices and a pressure fluid is supplied at a control pressure from a third pressure source to the control pressure chamber between the first pistons for simultaneously adjusting the pressures in the first and second secondary chambers and thereby the pressures in the first and second pressure activated devices.