Disclosed embodiments include hydraulic systems which provide power to lift, tilt and auxiliary (e.g., implement) functions, including high-flow auxiliary functions, with increased efficiency. Disclosed embodiments incorporate a single variable displacement pump that supplies pressurized fluid to a main control valve (e.g., for lift, tilt, and auxiliary functions) and a bypass circuit. The main control valve supplies fluid to control lift, tilt, and auxiliary flow for implements. The bypass circuit combines flow with the output of the auxiliary section of the main control valve to optionally provide high-flow for selected implements. The single variable displacement pump can then be set to different output flow levels, with the bypass circuit functioning differently under different conditions to optimize hydraulic flow to carryout various tasks under various conditions.

When a tilt in a right-and-left direction occurs in a cargo bed (9) being raised due to imbalance of excavated materials, the tilt is detected as a roll angle (θR), and it is determined whether the absolute value (|θR|) of the roll angle is not less than an imbalance determination value (θ2) (S4). When the absolute value is not less than the imbalance determination value (θ2) (Yes in S4) and the roll angle (θR) is positive (the cargo bed (9) is rising to the right) (Yes in S8), an oil supply amount (VL) to a hoist cylinder (11) on the left side is increased, and an oil supply amount (VR) to a hoist cylinder (12) on the right side is decreased (S9). When the roll angle (θR) is negative (the cargo bed (9) is rising to the left) (No in S8), the oil supply amount (VL) on the left side is decreased, and the oil supply amount (VR) on the right side is increased (S10).

An actuation pressure to actuate one or more hydraulic actuators may be determined based on a load on the one or more hydraulic actuators of a robotic device. Based on the determined actuation pressure, a pressure rail from among a set of pressure rails at respective pressures may be selected. One or more valves may connect the selected pressure rail to a metering valve. The hydraulic drive system may operate in a discrete mode in which the metering valve opens such that hydraulic fluid flows from the selected pressure rail through the metering valve to the one or more hydraulic actuators at approximately the supply pressure. Responsive to a control state of the robotic device, the hydraulic drive system may operate in a continuous mode in which the metering valve throttles the hydraulic fluid such that the supply pressure is reduced to the determined actuation pressure.

A hydraulic valve assembly includes a first spool valve and a first selector valve for actuating a first hydraulic consumer port or a second hydraulic consumer port, and a second spool valve and a second selector valve for actuating a third hydraulic consumer port or a fourth hydraulic consumer port. A shut-off valve is arranged in a common pressure channel. A branch channel with first and second pressure branch channels branches off the pressure channel upstream of the shut-off valve. The first selector valve connects the first pressure branch channel to a first connection line in a first switching position and connects the second pressure branch channel to a second connection line in a second switching position. The second selector valve, in a first switching position, connects the first connection line to the control channel and, in a second switching position, connects the second connection line to the control channel.

An actuation pressure to actuate one or more hydraulic actuators may be determined based on a load on the one or more hydraulic actuators of a robotic device. Based on the determined actuation pressure, a pressure rail from among a set of pressure rails at respective pressures may be selected. One or more valves may connect the selected pressure rail to a metering valve. The hydraulic drive system may operate in a discrete mode in which the metering valve opens such that hydraulic fluid flows from the selected pressure rail through the metering valve to the one or more hydraulic actuators at approximately the supply pressure. Responsive to a control state of the robotic device, the hydraulic drive system may operate in a continuous mode in which the metering valve throttles the hydraulic fluid such that the supply pressure is reduced to the determined actuation pressure.

This industrial apparatus (2) comprises a pneumatic system (4), a first mechanical device (36) and a second mechanical device (38). The pneumatic system (4) includes: a first pneumatic actuator (6) for commanding the first mechanical device (36), a second pneumatic actuator (8) for commanding the second mechanical device (38), a pneumatic control valve (10) switchable between several states to command of the first and second actuators (6, 8). The control valve (10) comprises an actuation portion (56), movable in translation between: a resting position, corresponding to a first state (51), a first pushed position, corresponding to a second state (S2), and a second pushed position, corresponding to a third state (S3). The first pushed position corresponds to an intermediary position between the resting position and the second pushed position.

An actuation pressure to actuate one or more hydraulic actuators may be determined based on a load on the one or more hydraulic actuators of a robotic device. Based on the determined actuation pressure, a pressure rail from among a set of pressure rails at respective pressures may be selected. One or more valves may connect the selected pressure rail to a metering valve. The hydraulic drive system may operate in a discrete mode in which the metering valve opens such that hydraulic fluid flows from the selected pressure rail through the metering valve to the one or more hydraulic actuators at approximately the supply pressure. Responsive to a control state of the robotic device, the hydraulic drive system may operate in a continuous mode in which the metering valve throttles the hydraulic fluid such that the supply pressure is reduced to the determined actuation pressure.

Disclosed embodiments include hydraulic systems which provide power to lift, tilt and auxiliary (e.g., implement) functions, including high-flow auxiliary functions, with increased efficiency. Disclosed embodiments incorporate a single variable displacement pump that supplies pressurized fluid to a main control valve (e.g., for lift, tilt, and auxiliary functions) and a bypass circuit. The main control valve supplies fluid to control lift, tilt, and auxiliary flow for implements. The bypass circuit combines flow with the output of the auxiliary section of the main control valve to optionally provide high-flow for selected implements. The single variable displacement pump can then be set to different output flow levels, with the bypass circuit functioning differently under different conditions to optimize hydraulic flow to carryout various tasks under various conditions.

A hydraulic valve assembly includes a connection section, a first valve section, at least one second valve section, and a hydraulic pilot control device with a pilot valve device. The first valve section has a first spool piston and a first spool diverter. The second valve section has a second spool piston and a second spool diverter. The first spool diverter and the second spool diverter are each switchable to at least a first spool diverter switching position and a second spool diverter switching position. Pilot pressure is applied in parallel to the first spool diverter and the second spool diverter via the hydraulic pilot control device in a first switching position of the pilot valve device for switching together into the first spool diverter switching position.

Different exemplary control systems for a hydraulically powered load-handling clamp, of the type usually mountable on industrial lift trucks or automatically guided vehicles, are disclosed. The disclosed systems variably limit a hydraulic force, by which load-clamping arms move a load substantially transversely, automatically depending on the weight of the load being moved, so as to avoid excessive transverse force applied to fragile loads.