A hydraulic machine. A high pressure line allows working fluid to flow into a hydraulic motor. A low pressure line allows working fluid to flow out of the hydraulic motor. High pressure line valves open and close the high pressure line. Low pressure line valves open and close the low pressure line. An operator input device inputs a command to control movement of the hydraulic motor. A control unit controls the high pressure line valves and the low pressure line valves to be opened and closed by receiving the command from the operator input device. The control unit controls the high pressure line valves to have a normalized flow factor K.sub.vHP, and controls the low pressure line valves to have a normalized flow factor K.sub.vLP, where K.sub.vLP<K.sub.vHP when a normalized flow factor K.sub.vcmd corresponding to the command is 0<K.sub.vcmd<1.

A hydraulic machine. A high pressure line allows working fluid to flow into a hydraulic motor. A low pressure line allows working fluid to flow out of the hydraulic motor. High pressure line valves open and close the high pressure line. Low pressure line valves open and close the low pressure line. An operator input device inputs a command to control movement of the hydraulic motor. A control unit controls the high pressure line valves and the low pressure line valves to be opened and closed by receiving the command from the operator input device. The control unit controls the high pressure line valves to have a normalized flow factor K.sub.vHP, and controls the low pressure line valves to have a normalized flow factor K.sub.vLP, where K.sub.vLP<K.sub.vHP when a normalized flow factor K.sub.vcmd corresponding to the command is 0<K.sub.vcmd<1.

Systems and apparatuses include a solenoid valve including a first coil, a second coil coupled to the first coil, a banjo fitting coupled to the second coil, a spool housing coupled to the banjo fitting so that the first coil and the second coil are selectively rotatable about the spool housing, a spool received within the spool housing, and an armature received within the first coil and the second coil and including a spool actuator coupled to the spool.

A method of controlling an actuator includes switching a primary solenoid valve to a first mode to fluidically connect a supply pressure source to a control chamber of a pilot valve. A fluid from the supply pressure source is directed through the primary solenoid valve to fill the control chamber of the pilot valve and put the pilot valve in a first position. The first position fluidically connects a second chamber of the actuator to a return pressure source. The actuator includes a cylinder between the first chamber and the second chamber and a rod attached to the cylinder. The fluid from the supply pressure source is directed into the first chamber of the actuator to move the cylinder and the rod in a first direction while the pilot valve is in the first position.

A method of controlling an actuator includes switching a primary solenoid valve to a first mode to fluidically connect a supply pressure source to a control chamber of a pilot valve. A fluid from the supply pressure source is directed through the primary solenoid valve to fill the control chamber of the pilot valve and put the pilot valve in a first position. The first position fluidically connects a second chamber of the actuator to a return pressure source. The actuator includes a cylinder between the first chamber and the second chamber and a rod attached to the cylinder. The fluid from the supply pressure source is directed into the first chamber of the actuator to move the cylinder and the rod in a first direction while the pilot valve is in the first position.

The invention relates to a construction machine, road milling machine, stabiliser, recycler, surface miner, and a to method for controlling a construction machine. The construction machine has a machine frame 2 supported by a chassis 1 and a plurality of hydraulic systems 15, 16, each of which has at least one hydraulic component 18, 22, at least one hydraulic pump 17, 21 for conveying hydraulic fluid for the at least one hydraulic component and at least one hydraulic line 28, 31 for transporting the hydraulic fluid from the at least one hydraulic pump to the at least one hydraulic component. The drive device of the construction machine comprises at least one internal combustion engine 24. A power transmission device 44 is provided for transmitting at least part of the drive power from the internal combustion engine 24 to the hydraulic pumps 17, 21. The construction machine according to the invention is characterised by a hydraulic control device 26, which is assigned to two hydraulic systems 15, 16 of the plurality of hydraulic systems. The hydraulic control device 16 is designed such that, in a special operating mode, at least part of the hydraulic fluid delivered by the hydraulic pump 17 of the one hydraulic system 15 is supplied to the other hydraulic system 16.

The invention relates to a construction machine, road milling machine, stabiliser, recycler, surface miner, and a to method for controlling a construction machine. The construction machine has a machine frame 2 supported by a chassis 1 and a plurality of hydraulic systems 15, 16, each of which has at least one hydraulic component 18, 22, at least one hydraulic pump 17, 21 for conveying hydraulic fluid for the at least one hydraulic component and at least one hydraulic line 28, 31 for transporting the hydraulic fluid from the at least one hydraulic pump to the at least one hydraulic component. The drive device of the construction machine comprises at least one internal combustion engine 24. A power transmission device 44 is provided for transmitting at least part of the drive power from the internal combustion engine 24 to the hydraulic pumps 17, 21. The construction machine according to the invention is characterised by a hydraulic control device 26, which is assigned to two hydraulic systems 15, 16 of the plurality of hydraulic systems. The hydraulic control device 16 is designed such that, in a special operating mode, at least part of the hydraulic fluid delivered by the hydraulic pump 17 of the one hydraulic system 15 is supplied to the other hydraulic system 16.

A bistable hydraulic solenoid valve has a valve spool that transitions between two positions, remaining in one of the two positions under an attractive magnetic force when the solenoids are not energized. The valve spool has a first permanent magnet attached to one end and a second permanent magnet attached to the other end, so that the first permanent magnet faces a first solenoid, and the second permanent magnet faces a second solenoid. The first solenoid is energized to have a first polarity, and the second solenoid is energized to have an opposite polarity to concurrently push and pull the valve spool within the valve body between a first position and a second position, the first position establishing a first flow path and the second position establishing a second flow path through the valve body and valve spool so as to enable flow of hydraulic fluid.

A single solenoid-controlled electro-hydraulic liftomatic system is provided. The single solenoid-controlled electro-hydraulic liftomatic system is developed for controlling electrically, automating a hydraulic mechanism used in three-point hitch systems of tractors lifted and lowered by a mechanically controlled hydraulic mechanism. The single solenoid-controlled electro-hydraulic liftomatic system includes an actuator, a hydraulic pump, a safety element, a tank line, a valve body, a hydraulic piston, at least one solenoid valve, a piston spring, a check valve, a time-delay relay, and a button.

A single solenoid-controlled electro-hydraulic liftomatic system is provided. The single solenoid-controlled electro-hydraulic liftomatic system is developed for controlling electrically, automating a hydraulic mechanism used in three-point hitch systems of tractors lifted and lowered by a mechanically controlled hydraulic mechanism. The single solenoid-controlled electro-hydraulic liftomatic system includes an actuator, a hydraulic pump, a safety element, a tank line, a valve body, a hydraulic piston, at least one solenoid valve, a piston spring, a check valve, a time-delay relay, and a button.