A system and method is provided for monitoring a hydraulic power system having at least one light emitter and a button. The method includes powering on the hydraulic power system, receiving an actuation at the button and detecting a release of the button after a first time interval, and entering a diagnostic state. The method further includes retrieving a code and displaying the code by turning on the emitter in a first pattern. In some embodiments, a system and method is provided for regulating a temperature of a hydraulic power system. In some embodiments, a system and method is provided for controlling operation of a hydraulic torque wrench.

It is made possible to suppress variations of the speed of an actuator into which a regeneration flow rate flows, regardless of variations of the regeneration flow rate caused by posture changes of the front part and to enhance the operability when the front part moves in the free fall direction, and hydraulic fluid discharged from an actuator driving the front part is regenerated. Accordingly, a controller 19 of a hydraulic system is provided with a regeneration control calculation section 19b, and a pump flow rate control calculation section 19c, and when the regeneration control calculation section controls a regeneration valve 12 to perform regeneration, the pump flow rate control calculation section controls a pump flow rate regulation device 20 to increase the delivery flow rate of a hydraulic pump 1 as the angle of an arm 16 approaches the vertically downward direction based on posture information about the arm 16 acquired by an inertial measurement unit 31.

A servo regulator includes a servo piston coupled with a swash plate, a pressure chamber provided to face an end portion of the servo piston, a spool configured to control a pressure in the pressure chamber by being moved by a solenoid, a biasing member configured to bias the spool against a thrust of the solenoid, and a feedback portion configured to change a biasing force of the biasing member in accordance with tilting of the swash plate, wherein the feedback portion is coupled with the swash plate via the servo piston.

A lift apparatus includes a lift assembly and a servo-control system. The lift assembly includes at least one pneumatic actuator including a movable member to provide a load to transfer a substrate between a support and a transfer plane. The lift assembly further includes at least one proportional pneumatic valve to control fluid flow between the actuator and a pressurized fluid supply or a vent, a plurality of pressure sensors each to measure pressure in a respective supply line to the actuator, and at least one position sensor to measure a position of the movable member. The servo-control system includes a controller to determine an output force based on a commanded force and an estimated force, generate a control signal based on the output force, and apply the control signal to the proportional valve to move the movable member.

A lift apparatus includes a lift assembly and a servo-control system. The lift assembly includes at least one pneumatic actuator including a movable member to provide a load to transfer a substrate between a support and a transfer plane. The lift assembly further includes at least one proportional pneumatic valve to control fluid flow between the actuator and a pressurized fluid supply or a vent, a plurality of pressure sensors each to measure pressure in a respective supply line to the actuator, and at least one position sensor to measure a position of the movable member. The servo-control system includes a controller to determine an output force based on a commanded force and an estimated force, generate a control signal based on the output force, and apply the control signal to the proportional valve to move the movable member.

A stage assembly (10) includes a stage (14), and a fluid actuator assembly (24) that moves the stage (14). The fluid actuator assembly (24) includes a piston housing (32) that defines a piston chamber (34); (ii) a piston (36) that separates the piston chamber (34) into a first chamber (34A) and a second chamber (34B); (iii) a supply valve (38C) that controls the flow of the working fluid (40) into the first chamber (34A); and (iv) an exhaust valve (38D) that controls the flow of the working fluid (40) out of the first chamber (34A). The supply valve (38C) has a supply orifice (250G) having a supply orifice area, and the exhaust valve (38D) has an exhaust orifice (352G) having an exhaust orifice area. Moreover, the supply orifice area is different from the exhaust orifice area. Further multiple valves of different sizes can be used in combination for the supply and exhaust for each chamber (34A), (34B).

A stage assembly (10) includes a stage (14), and a fluid actuator assembly (24) that moves the stage (14). The fluid actuator assembly (24) includes a piston housing (32) that defines a piston chamber (34); (ii) a piston (36) that separates the piston chamber (34) into a first chamber (34A) and a second chamber (34B); (iii) a supply valve (38C) that controls the flow of the working fluid (40) into the first chamber (34A); and (iv) an exhaust valve (38D) that controls the flow of the working fluid (40) out of the first chamber (34A). The supply valve (38C) has a supply orifice (250G) having a supply orifice area, and the exhaust valve (38D) has an exhaust orifice (352G) having an exhaust orifice area. Moreover, the supply orifice area is different from the exhaust orifice area. Further multiple valves of different sizes can be used in combination for the supply and exhaust for each chamber (34A), (34B).

A hydraulic system includes: a first hydraulic cylinder including a first volume chamber and a second volume chamber; a second hydraulic cylinder including a third volume chamber and a fourth volume chamber a first connection pipe that allows the first volume chamber and the third volume chamber to communicate with each other; a second connection pipe that allows the second volume chamber and the fourth volume chamber to communicate with each other; and a correction mechanism that corrects a position of the first piston by causing the first piston to advance or retreat in a state where the second piston is stationary, in which the correction mechanism includes a brake that regulates a movement of the second piston and, a bypass pipe that allows the first connection pipe and the second connection pipe to communicate with each other; and a valve that opens and closes the bypass pipe.

A hydraulic system includes: a first hydraulic cylinder including a first volume chamber and a second volume chamber; a second hydraulic cylinder including a third volume chamber and a fourth volume chamber a first connection pipe that allows the first volume chamber and the third volume chamber to communicate with each other; a second connection pipe that allows the second volume chamber and the fourth volume chamber to communicate with each other; and a correction mechanism that corrects a position of the first piston by causing the first piston to advance or retreat in a state where the second piston is stationary, in which the correction mechanism includes a brake that regulates a movement of the second piston and, a bypass pipe that allows the first connection pipe and the second connection pipe to communicate with each other; and a valve that opens and closes the bypass pipe.

To utilize and protect a mechanical load torque range of a servo drive in combination with a pump, a control unit is given a target system pressure as a reference variable and an actual system pressure as a control variable. An electric motor torque acting on a pump of the servo drive is specified by the control unit to an electric motor of the servo drive, a volume flow at the hydraulic load is generated by the pump, by which a mechanical load torque sets it at the electric motor and the actual system pressure is produced in the hydraulic load via the volume flow. A dynamic system variable of the hydraulic system is transmitted to the limiting unit. The limiting unit limits the motor torque transmitted by the control unit to the electric motor as a function of the value of the system variable