116 results about "Electro-hydraulic actuator" patented technology

The system includes a hydraulic powered actuator. A pump system having first and second hydraulic lines is coupled to the first and second ports, respectively and is capable of providing hydraulic fluid to either the first and second lines. First and second pressure sensors are coupled to the first and second lines, respectively. A third line is coupled between the first and second lines and includes first and second valves mounted in series therein. Preferably, the first and second valves are capable of latching in the open position. A reservoir is coupled to the third line between the first and second valves. A shut off valve is included for cutting off the flow from the reservoir.

A linear energy harvesting device that includes a housing and a piston that moves at least partially through the housing when it is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor drives an electric generator that produces electricity. Both the motor and generator are central to the device housing. Exemplary configurations are disclosed such as monotube, twin-tube, tri-tube and rotary based designs that each incorporates an integrated energy harvesting apparatus. By varying the electrical characteristics on an internal generator, the kinematic characteristics of to the energy harvesting apparatus can be dynamically altered. In another mode, the apparatus can be used as an actuator to create linear movement. Applications include vehicle suspension systems (to act as the primary damper component), railcar bogie dampers, or industrial applications such as machinery dampers and wave energy harvesters, and electro-hydraulic actuators.

The system includes a hydraulic surface actuator for operating a piston coupled to a structural member of an aircraft for moving the structural member. An electrical feedback sensor is coupled to the actuator piston rod. A summing circuit for receiving a command signal and the feedback signal is provided having an output which is coupled to a loop gain compensator for operating a servo motor. The shaft of the servo motor drives the shaft of a variable displacement pump having ports leading to the ports of the actuator. The variable displacement pump has a swash plate the angle of which is reduced by a hinge moment sensor and a de-stroking actuator when the load on the surface actuator exceeds a given percentage of maximum. A pump gain sensor measures the reduction in pump gain and produces an electrical output which is applied to the loop gain compensator to compensate for reduction in pump gain.

The invention discloses a direct-drive electro-hydraulic actuator which comprises a direct-drive electro-hydraulic servo pump, a pressurizing oil tank, a first oil compensation check valve, a second oil compensation check valve and a hydraulic cylinder; according to the direct-drive electro-hydraulic actuator, a plurality of oil supply units are combined for use, so that the direct-drive electro-hydraulic servo pump system can be combined for construction according to the power requirement of an integrated hydraulic system; and parts do not need to be designed independently, so that the system has higher flexibility. According to the direct-drive electro-hydraulic actuator, the plurality of oil supply units work simultaneously so as to form a heat backup of the direct-drive electro-hydraulic servo pump system, particularly, redundant configuration is carried out to the pump system; when one or a quantity of oil supply units fail, the other oil supply units can lead the pump system to degrade to work, and compared with the condition that the whole pump fails when a plunger of an axial plunger pump is pulled away or tightly clamped, the direct-drive electro-hydraulic servo pump system has higher reliability.

The invention discloses an electro-hydraulic actuator. The electro-hydraulic actuator comprises a servo motor, an oil pump, a three-position four-way electromagnetic directional valve, an oil cylinder, a displacement sensor, a controller and a proportional velocity regulating valve. The inlet of the proportional velocity regulating valve is communicated with the oil pump, the outlet of the proportional velocity regulating valve is communicated with a port P of the three-position four-way electromagnetic directional valve, and the proportional velocity regulating valve is electrically connected with the controller. When the electro-hydraulic actuator works, the servo motor, the oil pump and the proportional velocity regulating valve jointly act, hydraulic oil is conveyed into the oil cylinder, due to the fact that the proportional velocity regulating valve can stably control the output flow of a system in an infinitely small mode, the oil cylinder can be made to stably operate at very low speed, the defect that the oil pump can not stably output hydraulic oil in the low-speed operation process caused by factors of the oil pump itself is overcome, and locating accuracy of the oil cylinder is guaranteed.

The present invention provides an improvement for use in a wind turbine (20) having a plurality of variable-pitch blades (24) mounted on a hub (23) for rotation relative to a nacelle (22). The improvement broadly includes: a electro-hydraulic actuator (25) for controlling the pitch of one of the blades, the actuator including: a motor (26) adapted to be supplied with a current; a pump (27) driven by the motor and arranged to provide a hydraulic output as a function of the current supplied to the motor; and a hydraulic actuator (28) operatively arranged to selectively vary the pitch of the associated blade as a function of the hydraulic output of the pump; and wherein the motor, pump and actuator are physically arranged within the hub of the wind turbine.

The invention discloses a blade electro-hydraulic adjustment method and device of a high-oil-pressure control water turbine. A fuzzy mathematic model is established for a selected blade angle calculation method according to hydropower station hydrologic data and unit parameters. Then, a high-oil-pressure control blade adjustment electro-hydraulic actuator adjusts a rotating blade to the calculated angle according to changes of the water head and flow, and therefore high hydraulic energy conversion efficiency is obtained, and the target of the maximum annual energy output of a high-oil-pressure control blade angle rapid adjustment hydroelectric generating set is achieved. According to the key technology, a high-oil-pressure control system is adopted for the turbine blade adjustment actuator, a standard ball floating seal is adopted, and therefore the problem of oil leakage of a high-oil-pressure rotating sealing device is completely solved. The blade electro-hydraulic adjustment method and device fill in technical gaps in controlling blade adjustment by a Kaplan turbine through the high-oil-pressure speed controller system, and great technical innovation is achieved for the structural design of the water turbine.

The invention relates to the fault diagnosis field of an electro-hydraulic actuator, and discloses an on-line neural network fault diagnosis method based on data driving, which solves the problem thata database cannot be updated in real time in the traditional fault diagnosis of the actuator. The main points of the invention are as follows: analyzing the structure of an electro-hydraulic actuator, and building a simulation model of the electro-hydraulic actuator; analyzing the failure form of actuator, implanting different types of faults into the simulation model of electro-hydraulic actuator to complete the signal acquisition; collecting the data, extracting the eigenvalue and reduce the dimension; constructing the tag fault data matrix, and training the eigenvalues offline and online,so that the online neural network can be obtained. The electro-hydraulic actuator working data is acquired in real time, an on-line neural network is used to collect the data for fault diagnosis; after fault diagnosis, the collected data are trained on-line to update the on-line neural network. The invention is applicable to the fault diagnosis of the electro-hydraulic actuator.

The invention relates to a pump-control electro-hydraulic actuator, which comprises a position controller which is connected with a position sensor, the position sensor is connected with an expose head cylinder, two cavities of the expose head cylinder are respectively connected with the two ends of a hydraulic lock through a pipeline, the two ends of the hydraulic lock are connected with a two-way pump, a left relief valve, a right relief valve and a single valve, the other end of the check valves is connected and is connected with a fuel filter which is arranged in the oil box, the left relief valve and the right relief valve are connected with the oil box through the pipeline, an air filter and a liquid level thermometer are respectively arranged on the top portion and the side surface of the oil box, a distal control room is connected with a motor control unit through a wire, the two-way pump is connected with a motor, and the motor is connected with the motor control unit. The pump-control electro-hydraulic actuator leads the control room to adjust the motor control unit and adjust the rotating speed of the motor through a signal which is feedback to the position controller by a signal sensor, thereby adjusting the rotating speed of the two-way pump, achieving the changing of the two cavities of a hydro cylinder, and achieving the purpose of adjusting position. The pump-control electro-hydraulic actuator has low energy consumption, small volume, low cost and excellent control effect.

An electro hydraulic actuator with built-in fail safes is provided. Multiple accumulators are integrated into the actuator to improve reliability and redundancy. One or more accumulators can fail and the remaining accumulators provide sufficient energy to move the actuator to its fail-safe condition.

A method and apparatus for an electro-hydraulic actuator (1) having mechanical feedback provide closed loop control with a high degree of accuracy. The electro-hydraulic actuator (1) includes a current versus load generator (10), a single-stage servomechanism (20, 21, 22, 23), and a device (24, 25, 40, 41) for providing a mechanical feedback force for offsetting an input force (Fsol) of the current versus load generator (10).

The invention discloses a closed electro-hydraulic actuator. The closed electro-hydraulic actuator comprises an oil tank, an oil servo-motor, a filter mechanism, an energy storage mechanism, a cooler, an oil cylinder casing, a spring mechanism and a motor pump unit, wherein the oil servo-motor comprises an oil cylinder and an integration module. The oil cylinder is installed on the upper side of an oil cylinder top cover and arranged at the center of the inner cavity of the oil cylinder top cover, and the integration module is installed on the lower side of an oil tank top cover and corresponds to the position of the oil cylinder. A cylinder barrel of the oil cylinder is directly connected with the oil tank top cover in a sealed matching mode. The spring mechanism penetrating the inner cavity of the whole oil cylinder casing is installed outside the oil cylinder. One end of the spring mechanism is pressed on the upper side of the oil tank top cover, and the other end of the spring mechanism is connected with a piston rod of the oil cylinder. The extended end of the piston rod of the oil cylinder is connected with a displacement sensor. The closed electro-hydraulic actuator occupies a small area and is small in space size, convenient to install and quick and convenient to use, and mechanical connection in other modes does not exist except the mechanical connection at the valve position of a steam turbine set.

A compact chain cutting apparatus for automatically shearing and opening a chain link of a selected thickness in one operation is disclosed. The apparatus includes a housing, a first shearing member, a second shearing member, and an electro-hydraulic actuator system. The first shearing member is mounted to the housing. The second shearing member is pivotally mounted to the housing for movement to exert, in cooperation with the first shearing member, shearing and bending forces upon the chain link. The electro-hydraulic actuator system cooperates with the second shearing member to move automatically the second shearing member to shear and to bend the chain link, thereby defining an opening in the chain link greater than the thickness of the link.

The invention provides an electro hydraulic actuator for a butterfly valve. The electro hydraulic actuator comprises a shell, an electronic control part and a hydraulic system. The electronic control part comprises a controller, a displayer, control switches and an angle sensor, wherein the displayer, the control switches and the angle sensor are connected with the controller. The hydraulic system comprises a bidirectional gear quantitive hydraulic pump, an AC servo motor, one-way valves, a pressure oil tank, a double-liquid-control one-way valve, a gear rack type hydraulic cylinder and the butterfly valve. The AC servo motor is connected with the controller, and an output shaft of the AC servo motor is connected with an input shaft of the quantitive hydraulic pump. The pressure oil tank is communicated with a low-pressure oil suction port of the quantitive hydraulic pump through the one-way valves. Two outlets of the quantitive hydraulic pump are communicated with the hydraulic cylinder through the double-liquid-control one-way valve. The angle sensor is fixed to the upper portion of the hydraulic cylinder. One end, extending out of the hydraulic cylinder, of a rotation shaft is connected with a rotation shaft of the angle sensor. An output shaft of the hydraulic cylinder is connected with a rotation shaft of the butterfly valve. A hydraulic cylinder drive is high in response speed, the integration of the hydraulic cylinder is high, and the electro hydraulic actuator has high market competitiveness.

The invention discloses a foot-type robot knee joint with an embedded integrated electro-hydraulic actuator. An electro-hydraulic actuator, a piston rod, a p spring and a connecting rod are included;the integrated electro-hydraulic actuator is installed on a thigh rod, the hydraulic cylinder of the electro-hydraulic actuator is embedded in the upper portion of the thigh rod as an upper cavity, acavity is formed in the lower hollow portion of the thigh rod as a lower cavity, the piston rod is installed in the thigh rod, the upper end of the piston rod is located in the upper cavity, and the lower end of the piston rod is located in the lower cavity; the lower end of the connecting rod is hinged to a calf rod, the upper end of the connecting rod is hinged to the thigh rod through a circular boss. The controlling of the knee joint is convenient through simple mechanisms and cooperation, adjustable variable speed can be achieved, the piston rod can be prevented from bending moment damageand linear movement jamming, and the spring has a buffering effect and can prevent a robot body from being violently impacted.

The invention provides an electro-hydraulic actuator of a hydraulic integration machine, which comprises an electric control system, a hydraulic system, a hand operation mechanism, an oil tank and an oil cylinder, wherein the electric control system is connected with the hydraulic system, the hydraulic system is respectively connected with the hand operation mechanism and the oil tank, and the oil tank is connected with the oil cylinder. The invention is characterized in that the hydraulic system comprises an oil path and a hydraulic integration block, wherein one end of the hydraulic integration block is connected with the electric control system, the other end of the hydraulic integration block is connected with the hydraulic cylinder through a gear two-way pump, and the hydraulic cylinder is connected with a disc valve. Compared with the prior art, the electro-hydraulic actuator of the hydraulic integration machine of the invention can realize the regulation and the cut-off control of the valve, the huge hydraulic station of the hydraulic control system is omitted, the size is greatly reduced, the materials are saved, and the investment is reduced. The invention has the advantages of complete function, compact structure, small size, light weight, fast response and the like.

The invention relates to an electrohydraulic actuator comprising a body (1) that defines a cylindrical cavity (2) in which a piston (3) slides in leaktight manner and divides an inside volume of the cavity into two chambers (A, B) of variable volume, the piston being associated with at least one rod (4) passing in leaktight manner through an end wall of the cavity, the actuator including a bidirectional pump (5) having two ports (P1, P2), each connected to one of the chambers, an electric motor (8) for selectively driving the pump in one direction or the other, the pump being placed inside the piston of the actuator so as to move together therewith. According to the invention, the motor is placed at the end of the actuator and drives a shaft of non-circular section (6) extending through the cavity parallel to a sliding direction of the piston (3) and of the rod (4), the shaft passing through the piston (3) to co-operate with a complementary drive member (11; 21) of the pump that slides freely along the shaft during movements of the rod but that is driven in rotation when the shaft turns under drive from the electric motor.