Valve for use with hydraulic ram assemblies

A valve assembly for use in inhibition of fluid bypass through a piston or piston rod of a hydraulic ram assembly when a plurality of hydraulic ram assemblies are connected in series, said valve assembly including a valve body;

• a valve chamber provided in the valve body communicating with a pair of end bores constituting fluid access ports wherein each end bore is of restricted transverse dimension compared to the valve chamber and comprises a relatively narrow outer passage and an enlarged inner space;
• a pair of valve members each associated with a respective end bore and each of which are substantially T-shaped having an enlarged head portion adapted to seat in said enlarged inner space which functions as a valve seat for the adjacent valve member and a stem loosely fitted within said passage whereby in use each stem may extend outwardly from said bore's end;
• one of the projecting ends of the stem of the T comprising a longitudinal extending part which is retained within an accommodating passage of the piston, and a lateral cross member associated with said longitudinal extending part which extends through a transverse passage located within said piston rod and spaced therefrom with the ends of said lateral cross member being associated with an external collar surrounding the piston rod wherein said lateral cross member may impact against said transverse passage to thereby open a proximal access port when said external collar abuts a rod bush or wall of said hydraulic ram assembly;
• a pair of balls in said valve chamber separate from the valve members wherein, in use, each ball is held in abutting relationship with an adjacent head portion of a respective valve member, and
• a biassing member interposed between each of said balls in the valve chamber whereby each valve member is biassed outwardly to a closed and seated position, the construction and arrangement being such that each valve member may close or open a respective fluid access port to fluid flow through the valve chamber whereby in operation fluid flow into said chamber may occur only from the pressure side of the piston or piston rod accommodating said valve through said proximal access port wherein a distal access port is closed and whereby in response to said outwardly extended stem and prior to impact of said piston or piston rod upon an internal surface of the hydraulic ram assembly, said distal access port is opened to permit fluid flow to occur therethrough to the non-pressure side of the piston or piston rod from the valve chamber.