A hydraulic system for operating a rear gate of a baler implement includes a hydraulic cylinder having a housing that defines an interior, and a piston that is moveably disposed within the interior of the housing. The housing includes a first fluid port and a second fluid port, each disposed in fluid communication with a first fluid volume of the hydraulic cylinder. A flow rate control valve is moveable between a first position for directing fluid to or from the first fluid port at a first flow rate, and a second position for directing fluid to or from the second fluid port at a second flow rate. The second flow rate is different than the first flow rate.

A hydraulic system for a rear gate of a baler implement includes a fluid circuit having a first portion connected to and disposed in fluid communication with a first fluid port of a hydraulic cylinder. A flow bypass assembly is disposed in the first portion of the fluid circuit. The flow bypass assembly includes a flow rate control valve selectively moveable between a first position allowing fluid communication therethrough at a first flow rate, and a second position blocking fluid communication therethrough. The flow bypass assembly further includes a bypass passageway for circulating the fluid when the flow rate control valve is closed. A flow restriction is disposed within the bypass passageway to provide a second flow rate that is less than the first flow rate.

The present invention provides an improved high-low hydraulic system for compacting machinery, such as balers, horizontal balers, compactors, transfer station compactors, and the like. The high-low hydraulic system comprises at least one double rotary pump, a plurality of directional control valves, a pilot-operated back pressure reducing valve, a flow control valve, a plurality of one-way valves, and a plurality of pressure switches. The high-low hydraulic system may be regenerative or non-regenerative and provides many advantages over conventional hydraulic systems. Such advantages include greater system efficiency due to a reduced back pressure during the time of the retraction stroke and clever flow sequencing, mitigation of hydraulic shocks at the beginning and end of compaction and retraction strokes, and reduced cycle time of the cylinder during operation due to the concurrent filling of the rod end side during decompression of the blind end side after the compaction stroke. Moreover, the present high-low hydraulic system allows for the cylinder to operate at three or more independent speeds.

An example spool includes a spool body varying in diameter along a length of the spool body, thereby forming a plurality of lands of variable diameters, wherein a land of the plurality of lands is configured to control fluid flow from a workport passage formed in a valve worksection to a return cavity; and a plurality of axial grooves formed in a circular array about a circumference of the land, wherein the plurality of axial grooves comprises a first set of axial grooves and a second set of axial grooves, wherein an axial length of axial grooves of the second set of axial grooves is greater than a respective axial length of axial grooves of the first set of axial grooves, allowing the axial grooves of the second set of axial grooves to engage the return cavity before the axial grooves of the first set of axial grooves.

A valve system for use with a cylinder having an extensible rod, includes first and second valve assemblies, each including an inlet/outlet port configured to selectively be coupled with a source of pressurized gas, a check valve biased toward a closed state and having a check valve body at least partially receivable within a first port of the cylinder, a flow control valve positioned in series between the inlet/outlet port and the check valve, and an inlet pilot port connected with the check valve for opening the check valve when supplied with pressurized gas. First and second pilot lines extend to the respective inlet pilot ports from respective outlet pilot ports of the opposite ones of the first and second valve assemblies. When pressurized gas is supplied to the inlet/outlet port of a valve assembly, pressurized gas is also supplied to the opposite inlet pilot port.

1. Control Device

2. A control device for controlling a hydraulic consumer (2), such as a working cylinder, consisting of at least one control valve (18) having a control spool (20), which is guided in a valve housing (22) in a longitudinally movable manner and which can be actuated by means of an electric motor (24) and which can be controlled by means of control electronics (MC), which receive input signals from a sensor device (58, 60, 62), which detects at least one operating state of the consumer (2).

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 first fluid circuit is a fluid circuit of an air cylinder provided with an air cylinder with a first air chamber and a second air chamber that are defined by a piston; a switching valve that is switched between the drive step and return step of the piston; a first flow channel between the first air chamber and the switching valve; and a second flow channel between the second air chamber and the switching valve. Two speed control valves are provided in series in the second flow channel.

An air cylinder in which a flow rate controller is built in, has a head cover and a rod cover. A pilot air adjustment unit guides exhaust air to a switch valve of the flow rate controller as pilot air, and the switch valve is switched by an increase in the pressure of the pilot air.