Patent ID: 6782910
Filing Date: 2004-08-31
Classification: B66F,F15B,Y10T

Abstract:
A hydraulic valve assembly for selectably delivering hydraulic fluid from a supply of hydraulic fluid to one of a first hydraulic operator and a second hydraulic operator, said assembly comprising:a) a valve block defining: i) a first supply port adapted for fluid communication with said supply; ii) a second supply port adapted for fluid communication with said supply; iii) a first operator port adapted for fluid communication with said first hydraulic operator; iv) a second operator port adapted for fluid communication with said second hydraulic operator; v) a third operator port adapted for fluid communication with said first hydraulic operator; vi) a fourth operator port adapted for fluid communication with said second hydraulic operator; vii) a first chamber, said first chamber being in fluid communication with said first supply port, said first operator port, and said second operator port; viii) a second chamber, said second chamber being in fluid communication with said second supply port, said third operator port and said fourth operator port; b) a first selection valve located in said first chamber and a second selection valve located in said second chamber, said first and second selection valves being adapted to move in unison, said first and second selection valves operable between a first position when said hydraulic fluid is at a first pressure and a second position when said hydraulic fluid is at a second pressure, where in said first position, said first selection valve permits fluid communication between said first supply port and said first operator port, and said second selection valve permits fluid communication between said second supply port and said third operator port, where, in said second position, said first selection valve permits fluid communication between said first supply port and said second operator port, and said second selection valve permits fluid communication between said second supply port and said fourth operator port; wherein said first pressure is lower than said second pressure.