Patent ID: 8584704

Claim:
A valve assembly configured for controlling fluid flow between a first reservoir and a second reservoir, the valve assembly comprising: a relief valve configured to open a first fluid flow path when a pressure inside the first reservoir is above a first predetermined pressure value; a solenoid assembly configured to open a second fluid flow path when a rate of the fluid flow from the first reservoir to the second reservoir is above a predetermined reference value; a housing defining the first and second fluid flow paths; and a flow restrictor configured to open a third fluid flow path when the rate of the fluid flow from the first reservoir to the second reservoir is below the predetermined reference value, and also when the pressure inside the first reservoir is below a second predetermined pressure value; wherein: the relief valve and the solenoid assembly are arranged inside the housing; the solenoid assembly includes an armature configured to selectively open and close the flow restrictor, a solenoid spring configured to generate a force sufficient to close the restrictor by displacing the armature, and a coil configured to energize the armature, overcome the solenoid spring, and thereby open the restrictor; and the solenoid spring is configured to generate a force sufficient to close the third fluid flow path when the pressure inside the first reservoir is a positive value, but insufficient to close the third fluid flow path when the pressure inside the first reservoir is a negative value.