Fluid regeneration circuit for hydraulic cylinders

A fluid regeneration circuit for a hydraulic system having a hydraulic actuating cylinder, the actuating cylinder having a head end portion, a rod end portion, and a piston movable therewithin, the regeneration circuit comprising:

• a control valve connected in fluid communication with the head and rod end portions of the actuating cylinder for controlling the operation thereof;
• a regeneration valve connected in fluid communication with said control valve and with the head and rod end portions of the actuating cylinder, said regeneration valve being operable in one position thereof to allow fluid flow to flow therethrough from the rod end portion of the actuating cylinder to said control valve for distribution to other portions of the hydraulic system, said regeneration valve being operable in another position to allow fluid flow therethrough from the rod end portion of the actuating cylinder to the head end portion of the actuating cylinder;
• a position sensor coupled to the actuating cylinder for sensing the position of the piston within the actuating cylinder during movement thereof and generating a signal indicative of said position;
• a controller coupled to said position sensor for receiving signals therefrom, said controller being operable to receive signals from said position sensor and thereafter determine the velocity of said piston based upon the signals outputted by said position sensor;
• said controller being coupled to said control valve and being operable to output signals thereto for controlling fluid flow to and from the respective head and rod end portions of the actuating cylinder;
• said controller being further coupled to said regeneration valve and being operable to output signals thereto in response to the signals received from said position sensor, said controller outputting a signal to said regeneration valve to allow fluid flow from the rod end portion of the actuating cylinder through said regeneration valve to the head end portion of the actuating cylinder when the velocity of the piston is determined to be above a first predetermined threshold velocity, said controller outputting a signal to the regeneration valve to allow fluid flow from the rod end portion of the actuating cylinder through said regeneration valve to said control valve when said controller determines that the velocity of said piston is below a second predetermined threshold velocity.

A fluid regeneration circuit for a hydraulic system having at least one hydraulic actuator mechanism associated therewith for controlling movement of a work element, said actuator mechanism having an expanding side, a contracting side, and a member moveable by the actuator mechanism, the regeneration circuit comprising:

• a regeneration valve connected in fluid communication with the expanding and contracting sides of the actuator mechanism, said regeneration valve having an inlet port connected in fluid communication with the contracting side of the actuator mechanism via a first fluid path, said regeneration valve having a first outlet port connected in fluid communication with the hydraulic system via a second fluid path, said regeneration valve having a second outlet port connected in fluid communication with the expanding side of the actuator mechanism via a third fluid path;
• a position sensor coupled to the actuator mechanism for determining the position of the movable member;
• and
• a controller coupled to said position sensor for receiving signals therefrom, said controller being operable to receive signals from said position sensor indicative of the position of the moveable member, said controller being further operable to determine the velocity of said moveable member based upon the signal outputted by said position sensor;
• said controller being coupled to said regeneration valve and being operable to output signals thereto in response to the signals received from said position sensor, said controller outputting a signal to said regeneration valve to allow fluid flow from said regeneration valve through said third fluid path to the expanding side of the actuator mechanism when the velocity of the moveable member is determined to be above a first predetermined threshold velocity, said controller outputting a signal to the regeneration valve to allow fluid flow from said regeneration valve through said second fluid path when said controller determines that the velocity of the moveable member is below a second predetermined threshold velocity.

A fluid regeneration circuit for a hydraulic system having at least one hydraulic actuating cylinder associated therewith, said actuating cylinder having a head end portion, a rod end portion, and a piston movable therewithin, the regeneration circuit comprising:

• a regeneration valve connected in fluid communication with the head and rod end portions of the actuating cylinder, said regeneration valve having an inlet port connected in fluid communication with the rod end portion of the actuating cylinder via a first fluid path, said regeneration valve having a first outlet port connected in fluid communication with the hydraulic system via a second fluid path, said regeneration valve having a second outlet port connected in fluid communication with the head end portion of the actuating cylinder via a third fluid path;
• a first sensor coupled to the actuating cylinder adapted to sense a parameter indicative of a velocity of said piston, said sensor generating a first sensor signal;
• and
• a controller coupled to said first sensor for receiving signals therefrom, said controller being operable to receive signals from said first sensor indicative of the velocity of the piston within the actuating cylinder during movement thereof and responsively determining a cylinder velocity;
• said controller being coupled to said regeneration valve and being operable to output signals thereto in response to the signals received from said first sensor, said controller outputting a signal to said regeneration valve to allow fluid flow from said regeneration valve through said third fluid path to the head end portion of the actuating cylinder when the velocity of the piston is determined to be above a first predetermined threshold velocity.

A method of regenerating fluid in a hydraulic circuit, the circuit having at least one hydraulic actuating cylinder, the cylinder having a head end portion and a rod end portion, and a piston moveable therewithin, the circuit having a regeneration valve connected in fluid communication with the head end and rod end portions of the actuating cylinder, the regeneration valve having an inlet port connected in fluid communication with the rod end portion of the actuating cylinder via a first fluid path, said regeneration valve having a first outlet port connected in fluid communication with the hydraulic system via a second fluid path, said regeneration valve having a second outlet port connected in fluid communication with the head end portion of the actuating cylinder via a third fluid path, the hydraulic circuit including an operator input device connected to a controller, the controller being controllably connected to the regeneration valve, comprising the steps:

• sensing a first parameter indicative of a piston velocity and responsively generating a first sensed signal;
• sensing a second parameter indicative of an operator desired command and responsively generating a second sensed signal;
• determining said piston velocity in response to said first signal;
• determining said operator command in response to said second signal;
• and
• triggering said regeneration when said piston velocity is greater than a velocity threshold and said operator command is greater than a command threshold.