Hydraulically controlled self-contained multifunctional tool such as shears/separator

A hydraulically controlled self-contained multi-functional tool of the type having a hydraulic ram portion, a rod assembly portion, and an active tool member constituted by two blades which are articulated about a common pin and which are mounted on a fork joint that is securely fixed to the ram portion of the tool, the opening and closing of the blades being achieved by a system of links controlled by the rod assembly of the tool, the rod assembly being of the type having a leak-tight chamber containing a fluid and an electric motor partially surrounded by the chamber, the motor being powered by a battery and connected to drive means for compressing the fluid contained within the leak-tight chamber;

• the improvement comprising:
• flexible membrane means being arranged in the leak-tight chamber around the electric motor for compensating for volume differences of the fluid in the chamber and for avoiding the formation of a vacuum within the chamber when fluid is moved to activate the blades of the tool;
• a single piston having a first face and a second face contained within a cylinder that is positioned within the ram portion of the tool, said piston being connected to the system of links that is connected to the blades of the tool;
• a closed reversible fluid circuit fluidly connecting the leak-tight chamber to the first and second faces of said single piston;
• and
• a directional control and feeder valve contained within said closed reversible fluid circuit that allows compressed fluid from the leak-tight chamber to be directed with equal force against either the first face of said single piston thereby closing the blades of the tool or the second face of said single piston thereby opening the blades of the tool.