Abstract: A spool is disclosed for use in a valve. The spool may have an elongated cylindrical body with a first end and a second end. The spool may also have a first land formed at the first end, a second land axially spaced apart from the first land, and a check element located between the first and second lands. The check element may have an outer diameter that is about 0.5-1% greater than an outer diameter of the second land.

Abstract: A spool is disclosed for use in a valve. The spool may have an elongated cylindrical body with a first end and a second end. The spool may also have a first land formed at the first end, a second land axially spaced apart from the first land, and a check element located between the first and second lands. The check element may have an outer diameter that is about 0.5-1% greater than an outer diameter of the second land.

Abstract: A void protection system for a mining shovel having an operator input device includes an independent metering valve assembly including one or more fluid source-cylinder valves for fluidly connecting the fluid source to the hydraulic cylinder. The system also includes a sensor assembly for monitoring the fluid pressure within the rod end and the head end of the hydraulic cylinder, and a control module. The control module is configured to monitor movement of the operator input device, monitor pressure within the hydraulic cylinder, increase the opening of the corresponding fluid source-cylinder valve and increase fluid flow from the fluid source to fill corresponding end of the hydraulic cylinder until pressure in the corresponding end of the hydraulic cylinder is above a first threshold pressure.

Abstract: A hydraulic control system is disclosed. The hydraulic control system may have a pump configured to pressurize a fluid, an actuator, a position sensor associated with the actuator and configured to generate a first signal indicative of a position of the actuator, and a circuit fluidly connecting the pump to the actuator. The hydraulic control system may also have a valve associated with the circuit and configured to move from a first position, at which fluid relief from the circuit is inhibited, toward a second position, at which fluid is relieved from the circuit through the valve, when a pressure of fluid within the circuit exceeds a threshold setting of the valve. The hydraulic control system may additionally have a controller in communication with the position sensor and the valve. The controller may be configured to selectively cause adjust the threshold setting of the valve based on the first signal.

Abstract: A void protection system for a mining shovel having an operator input device includes an independent metering valve assembly including one or more fluid source-cylinder valves for fluidly connecting the fluid source to the hydraulic cylinder. The system also includes a sensor assembly for monitoring the fluid pressure within the rod end and the head end of the hydraulic cylinder, and a control module. The control module is configured to monitor movement of the operator input device, monitor pressure within the hydraulic cylinder, increase the opening of the corresponding fluid source-cylinder valve and increase fluid flow from the fluid source to fill corresponding end of the hydraulic cylinder until pressure in the corresponding end of the hydraulic cylinder is above a first threshold pressure.

Abstract: A hydraulic system for a machine is disclosed. The hydraulic system may have a first pump with variable displacement and being load-sense controlled, and a first hydraulic circuit associated with the first pump. The hydraulic system may also have a second pump with variable displacement and being electro-hydraulically controlled, and a second hydraulic circuit associated with the second pump. The hydraulic system may further have a flow-sharing valve arrangement configured to selectively share fluid flow between the first and second hydraulic circuits.

Abstract: A computer-based method for calibrating a solenoid-controlled excess flow control valve that couples a first hydraulic circuit to a second hydraulic circuit is provided. The method includes determining a start-of-flow current at which hydraulic fluid begins to flow, closing the valve, sending an actuator command to the second hydraulic circuit, determining a first flow through the hydraulic actuator, opening the valve by setting the solenoid current to a calibration-flow current, sending the actuator command to the second hydraulic circuit, determining a second flow through the hydraulic actuator, calculating a flow difference, determining a calibration-flow valve command associated with the flow difference, determining a maximum-flow current based on the start-of-flow current, the calibration flow current, and the calibration-flow valve command, and creating a valve calibration table based on the start-of-flow current, the maximum-flow current and a valve response table.

Abstract: A hydraulic control system is disclosed. The hydraulic control system may have a pump configured to pressurize a fluid, an actuator, a position sensor associated with the actuator and configured to generate a first signal indicative of a position of the actuator, and a circuit fluidly connecting the pump to the actuator. The hydraulic control system may also have a valve associated with the circuit and configured to move from a first position, at which fluid relief from the circuit is inhibited, toward a second position, at which fluid is relieved from the circuit through the valve, when a pressure of fluid within the circuit exceeds a threshold setting of the valve. The hydraulic control system may additionally have a controller in communication with the position sensor and the valve. The controller may be configured to selectively cause adjust the threshold setting of the valve based on the first signal.

Abstract: A filter assembly is disclosed having a filter base including an inlet and an outlet. The filter assembly also has a first valve disposed in the inlet, the first valve including a portion that protrudes from the filter base. The filter assembly additionally has a second valve disposed in the outlet, the second valve including a portion that protrudes from the filter base. The filter assembly also has a removably attachable filter configured to mechanically bias the first and second valves in an open position.

Abstract: A hydraulic system for a machine is disclosed. The hydraulic system may have a first pump with variable displacement and being load-sense controlled, and a first hydraulic circuit associated with the first pump. The hydraulic system may also have a second pump with variable displacement and being electro-hydraulically controlled, and a second hydraulic circuit associated with the second pump. The hydraulic system may further have a flow-sharing valve arrangement configured to selectively share fluid flow between the first and second hydraulic circuits.