Patent ID: 6062260
Filing Date: 2000-05-16
Classification: F15B,Y10T

Abstract:
A dual piston pilot valve comprising:a housing forming first and second cylinders,a first piston having a first seal region and moveable in the first cylinder,a first spool moveable in the first cylinder for engaging the first piston to effect movement of the first piston,a second piston having a second seal region and moveable in the second cylinder,a second spool moveable in the second cylinder for engaging the second piston to effect movement of the second piston,a single pressurized fluid supply port communicating with both the first and second cylinders,a first output port communicating with the first cylinder,a second output port communicating with the second cylinder,a single exhaust port communicating with both the first and second cylinders,a diaphragm engaging the housing and both the first and second pistons, the diaphragm being positioned between both the first and second spools and both the first and second seal regions of the first and second pistons to effect a seal between the single exhaust port and the first and second spools,a first control valve communicating with the single pressurized fluid supply port to move the first piston to open fluid passage between the single pressurized fluid supply port and the first output port and communicating with the first cylinder to move the first piston to open fluid passage between the single exhaust port and the first output port, anda second control valve communicating with the single pressurized fluid supply port to move the second piston to open fluid passage between the single pressurized fluid supply port and the second output port and communicating with the second cylinder to move the second piston to open fluid passage between the single exhaust port and the second output port,wherein the first control valve effects movement of the first piston independent of the movement of the second piston, and the second control valve effects movement of the second piston independent of the movement of the movement of the first piston.