Hydraulic system with cross function regeneration

In a hydraulic system having a pump connected to a prime mover, a tank, first actuator, a first control valve assembly which controls flow of fluid from the pump to the first actuator and from the first actuator to the tank, a second actuator;

• and a second control valve assembly which controls flow of fluid from the pump to the second actuator and from the second actuator to the tank;
• a regeneration system comprising:
• a proportional regeneration regulation valve coupling a tank outlet of the first control valve assembly to the tank;
• a first isolation valve coupling the tank outlet of the first control valve assembly to a pump inlet of the second control valve assembly;
• a first pressure sensor connected to the first actuator and providing an indication of a first pressure;
• a second pressure sensor connected to the second actuator and providing an indication of a second pressure;
• and
• a system controller having inputs connected to the first pressure sensor and the second pressure sensor, and having outputs connected to the regeneration regulation valve and the isolation valve, wherein when fluid is being drained under pressure from the first actuator the system controller at least partially closes the regeneration regulation valve and opens the isolation valve in response to the first pressure being greater than the second pressure, thereby driving the second actuator with the fluid being drained from the first actuator.

A regeneration method for a hydraulic system having a prime mover connected to a pump to supply hydraulic fluid under pressure, a first actuator and a second actuator, said regeneration method comprising the steps of:

• draining hydraulic fluid under pressure from the first actuator;
• sensing pressure of the hydraulic fluid drained from the first actuator to produce an indication of a first pressure;
• selecting among a first mode of operation, a second mode of operation, and a third mode of operation:
• in the first mode of operation:
• (a) sensing pressure of the hydraulic fluid at an inlet of the second actuator to produce an indication of a second pressure, and
• (b) in response to the first pressure being greater than the second pressure, routing hydraulic fluid drained from the first actuator to the inlet of the second actuator to drive the second actuator;
• in the second mode of operation:
• (c) when the pump is not supplying pressurized fluid to an actuator of the hydraulic system, routing hydraulic fluid drained from the first actuator to an outlet of the pump thereby causing the pump to drive the prime mover;
• and
• in the third mode of operation:
• (d) sensing pressure of the hydraulic fluid in an accumulator to produce an indication of a third pressure, and
• (e) in response to the first pressure being greater than the third pressure, storing the hydraulic fluid drained from the first actuator in the accumulator.

In a hydraulic system having a pump connected to a prime mover, a tank, first actuator, and a second actuator;

• a regeneration system comprising:
• supply line coupled to the pump;
• a first control valve which connects the supply line to the first actuator and controls flow of fluid in either direction there between;
• a second control valve which is unidirectional and controls flow of fluid from the first actuator to the tank,
• a third control valve which is unidirectional and connects the supply line to the second actuator;
• a fourth control valve which is unidirectional and controls flow of fluid from the second actuator to the tank,
• a first pressure sensor connected to the first actuator and providing an indication of a first pressure;
• a second pressure sensor connected to the second actuator and providing an indication of a second pressure;
• and
• a system controller having inputs connected to the first pressure sensor and the second pressure sensor, and having outputs connected to the first control valve, the second control valve, the third control valve, and the fourth control valve, wherein when fluid is being drained under pressure from the first actuator the system controller opens the third control valve and at least partially opens the first control valve in response to the first pressure being greater than the second pressure thereby driving the second actuator with the fluid being drained from the first actuator.

In a hydraulic system having a pump connected to a prime mover, a tank, an actuator, and a double acting cylinder having a first chamber and a second chamber;

• a regeneration system comprising:
• supply line coupled to the pump;
• a first control valve which connects the supply line to the first chamber of the double acting cylinder;
• a second control valve which controls flow of fluid from the first chamber of the double acting cylinder to the tank;
• a first bidirectional pilot operated control valve which connects the supply line to the second chamber of the double acting cylinder;
• a third control valve which controls flow of fluid from the second chamber of the double acting cylinder to the tank;
• a second bidirectional-pilot operated control valve which connects the supply line to the actuator;
• a fourth control valve which controls flow of fluid from the actuator to the tank;
• a first pressure sensor connected to the first chamber of the double acting cylinder and providing an indication of a first pressure;
• a second pressure sensor connected to the second chamber of the double acting cylinder and providing an indication of a second pressure;
• a third pressure sensor connected to the actuator and providing an indication of a third pressure;
• and
• a system controller having inputs connected to the first pressure sensor and the second pressure sensor, and having outputs connected to the first bidirectional control valve, the second bidirectional control valve, the first control valve, the second control valve, the third control valve, and the fourth control valve;
• wherein when fluid is being drained under pressure from the second chamber of the double acting cylinder, the system controller at least partially opens the first bidirectional control valve and the second bidirectional control valve in response to the first pressure being greater than the second pressure, thereby driving the actuator with the fluid being drained from the second chamber;
• and
• wherein when fluid is being drained under pressure from the actuator, the system controller at least partially opens the second bidirectional control valve and one of the first bidirectional control valve and the first control valve, thereby driving the double acting cylinder with the fluid being drained from the actuator.

In a hydraulic system having a pump connected to a prime mover, a tank, a double acting cylinder having a first chamber and a second chamber, and an actuator, a regeneration system comprising:

• a first control valve which connects the pump to the first chamber of the double acting cylinder;
• a second control valve which controls flow of fluid from the first chamber of the double acting cylinder to the tank;
• a bidirectional control valve which connects the pump to the second chamber of the double acting cylinder;
• a third control valve which controls flow of fluid from the second chamber of the double acting cylinder to the tank;
• a fourth control valve which connects the pump to the actuator;
• a fifth control valve which controls flow of fluid from the actuator to the tank;
• and
• a system controller having outputs connected to the bidirectional control valve, the first control valve, the second control valve, and the third control valve;
• wherein when fluid is being drained under pressure from the second chamber of the double acting cylinder, the system controller enters one of a first mode and a second mode, in the first mode the first control valve and the bidirectional control valve are opened thereby supplying the first chamber with fluid from the second chamber, and in the second mode the first bidirectional control valve and the fourth control valve are opened, thereby driving the actuator with the fluid being drained from the second chamber.