Abstract: An electrohydraulic system for use under water includes an electrohydraulic actuator and a container. A hydraulic cylinder or a hydraulic motor and a hydraulic machine are arranged in an internal space of the container. The hydraulic machine is mechanically coupled to a rotary drive unit for a common rotary movement, and the hydraulic machine adjusts the hydraulic cylinder or the hydraulic motor. The rotary drive unit is arranged outside the container and is configured to couple to and decouple from the hydraulic machine. A device in one embodiment includes the electrohydraulic system.

Abstract: A method, system and apparatus including a mechanism capable of performing a variety of operations, each operation having a respective power requirement and a power source capable of providing power to the mechanism at a variety of different levels corresponding to the operations being undertaken by the mechanism where the power source is regulated to at least provide a first lower power level sufficient for one or more operations requiring a lower power level and is increased to provide a higher power level as needed for one or more alternative operations requiring a higher power level.

Abstract: A hydraulic engine which may generate rotational power by using environmentally friendly electric energy and have improved performance and a long life span, and more particularly, environmentally friendly hydraulic power units that that may extrude a working fluid to realize an engine and has a long life span. The hydraulic engine includes: a housing; a rotor that is rotatably supported in the housing and allows rotor blades to be disposed therearound; a plurality of hydraulic power units that are disposed around the rotor to be spaced apart from one another; and an output shaft that rotates as the rotor rotates and the output shaft protrudes beyond the housing, wherein a fluid extruded from hydraulic power units pressurizes the rotor blades and generates a rotational force of the output shaft.

Abstract: Disclosed is a hydraulic system for a hydraulic excavator. The hydraulic system inputs rotary power from a rotary power producing means to a hydraulic pump to produce hydraulic power, and operates an actuator by the hydraulic power. A hydraulic oil drain line from the actuator is branched into a flow rate control line as a line connected to a spool of a flow rate control valve controllable by manipulation of a lever and a power regeneration line as a line connected to a variable displacement motor for converting hydraulic power of discharged hydraulic oil to reusable energy. A regeneration ratio control means is also arranged to control the variable displacement motor such that a flow rate of the power regeneration line satisfies a preset fixed ratio ? relative to a flow rate occurred in the flow rate control line by the manipulation of the lever.

Abstract: A pendulum absorber assembly for a torque converter including a first spring retainer, a second spring retainer, and a floating flange positioned between the first spring retainer and the second spring retainer. The pendulum absorber assembly also includes a drive plate affixed to the floating flange, a plurality of arcuate springs disposed between the second spring retainer and the drive plate, and a plurality of pendulum weights affixed to the second spring retainer, wherein the pendulum weights are made of tungsten alloy.

Abstract: A controllable brake booster and to a method and a device for controlling the brake booster are disclosed. The pedal force that a driver must apply in order to convey an input element of the brake booster into an actuating position or to retain the element in said position is adjusted by operating the brake booster.

Abstract: An advancing assembly for underground powered shield support having at least one floor skid for supporting the powered shield support, an advancing beam and a substantially perpendicularly arranged lift cylinder for lifting the floor skid relative to the advancing beam during an advancing movement. The lift cylinder has a cylinder foot supported above the advancing beam and a cylinder head buttressed on a bridge and hydraulically displaceable relative to the cylinder foot. In order to improve a powered shield support and in particular the advancing assembly of a powered shield support, the lift cylinder is a double lift cylinder having a first cylinder stage, comprising the cylinder head, and a second cylinder stage, wherein a compression spring is arranged between the cylinder stages.

Abstract: A hydraulic drive type working vehicle, with speedy responsiveness in an excavating operation, includes: a pouring changeover valve (10), which is switchable between (a) a pouring position, wherein pressurized oil of a travel hydraulic circuit (5) is poured into a working machine hydraulic circuit (8), and (b) a shutoff position, wherein the travel hydraulic circuit (5) and the working machine hydraulic circuit (8) are isolated from each other; a first changeover valve (16), which is switchable from its shutoff position to its communicating position when the oil pressure of the travel hydraulic circuit (5) exceeds a predetermined oil pressure; a pouring command switch (14); and a second changeover valve (17), which is connected in series with the first changeover valve (16) and which is switchable from its shutoff position to its communicating position upon receipt of a pouring command from the pouring command switch (14); and wherein the pouring changeover valve (10) is switchable to the pouring position whe

Abstract: An engine revolution speed control device according to the present invention comprises: a hydraulic pump (1) which is driven by an engine (21); a hydraulic motor (4) for vehicle movement which is driven by oil expelled from the hydraulic pump (1) during vehicle movement; an actuator (52) for working which is driven by the oil expelled from the hydraulic pump (1) during the working state; a vehicle driving pedal (6) which during vehicle movement controls vehicle speed according to its amount of operation; a means (33) for speed reduction decision which makes a decision as to whether the amount by which the vehicle driving pedal (6) is depressed is being reduced; and a means for revolution speed control (33).

Abstract: Apparatus is for controlling load on an engine, particularly a marine engine powering a controllable pitch propeller which serves as an engine loading device. Apparatus cooperates with a circuit having a supply fluid at a constant supply pressure, and a control fluid at a variable control pressure reflecting engine load. The apparatus has a signal receiver to receive a load demand signal from an operator, and a positioner apparatus with a positioner output which cooperates with the loading device of the engine. The positioner apparatus receives the supply and control fluids and has a partition separating the fluids to permit interaction therebetween to control the positioner output. The apparatus has a hydraulic fluid valve to control flow of hydraulic fluid relative to the positioner apparatus, the fluid valve being connected to the positioner output and an output of the signal receiver so as to be responsive to relative positions of both outputs.

Abstract: An actuator system is disclosed which modulates a linear output shaft associated with a working control valve or the like in response to a control signal input. The system includes a feedback control link, a pneumatic positioner, a pneumatically controlled hydraulic valving system and a hydraulic cylinder and piston assembly controlled by the hydraulic valving system. The hydraulic valving system includes a three-position, four-way valve actuated by pneumatic binary output signals from a signal conditioner which is in turn controlled by the positioner. Hydraulic flow to the three-position, four-way valve may also be controlled from the signal conditioner in response to positioner output for most effective actuation of the hydraulic cylinder and piston assembly. Failure modes are also disclosed with the present system. The resulting system exhibits extremely rapid response times and high accuracy with dynamic stability.

Abstract: A tractor hydraulic control system of the kind comprising a power lift with a hydraulic actuator (12) and a main control valve (17) controlling the supply of fluid from a pump (19) to the actuator, the system including selector valve means (50) interconnected with the main control valve (17) and movable between a first position in which flow to and from the actuator (12) occurs via the selector valve means under the control of the main control valve and the associated system control mechanism (28) and a second position in which the actuator is hydraulically locked in a given position and an external services outlet (51) is placed in communication with the pump. Linkage means (60,61,62) operatively connects the selector valve means (50) and the system control mechanism (28) to condition the main control valve (17) to cause the pump (19) to supply fluid to the external service outlet (51) via the selector valve means on movement of the selector valve means to the second position.

Abstract: A pneumatic control system for machines that provides precise incremental or continuous direction, position, velocity and acceleration control of a variety of machine functions, such as rotary or linear motions, tool positioning and the like. A compressed air supply is maintained accurately at a preselected minimum pressure necessary for a particular operation, by a digitally pulsed air flow control system. Air flow and pressure to the associated actuating mechanisms is also controlled by a digital dithering technique using individual sharp pulses of air, each of which instantly breaks the static friction of the mechanism and causes a discrete precise increment of movement, with rapid consecutive pulses providing continuous motion. The direction, amount, acceleration and speed of travel are controlled by varying the pulse width and rate of air flow and pressure as necessary and for efficiency in air consumption.

Abstract: Disclosed is a tilt cab truck in which the weight of the cab is partially supported by the tilting cylinder while the cab is in the over-the-road position. A fluid-by-pass circuit is provided to permit the cab to perform limited up-and-down movement relative to the frame of the truck.

Abstract: An actuator system is disclosed which modulates a linear output shaft associated with a working control valve or the like in response to a control signal input. The system includes a feedback control link, a pneumatic positioner, a pneumatically controlled hydraulic valving system and a hydraulic cylinder and piston assembly controlled by the hydraulic valving system. The hydraulic valving system includes a three-position, four-way valve actuated by pneumatic binary output signals from a signal conditioner which is in turn controlled by the positioner. Hydraulic flow to the three-position, four-way valve may also be controlled from the signal conditioner in response to positioner output for most effective actuation of the hydraulic cylinder and piston assembly. Failure modes are also disclosed with the present system. The resulting system exhibits extremely rapid response times and high accuracy with dynamic stability.

Abstract: To permit mechanical override of an electrical command system to control deflection of the swash plate or eccentricity of an axial or radial piston pump, for example upon failure of the electrical control system, a group of valves 5-8 are connected to an electrical control unit 23 and an additional control valve 4, 4' with a manual control lever 18', 30' is provided, the deflection of the swash plate 1 or eccenter ring 28 of the pump being sensed by a position transducer 22 moved by a linkage which includes the manual control lever. In normal operation, the manual control lever is maintained by spring pressure to deactivate the control valve but, under emergency conditions, the manual control lever will operate the first control valve 4, 4' to admit hydraulic control fluid to position the swash plate, or eccenter ring, respectively, the consequent movement of which is fed back through the linkage to the manual control lever.

Abstract: A power steering device includes a housing which couples to a pressure source in order to provide a power assist to the rotation of an output member upon rotation of an input member. The input member and the output member are rotatably supported within a housing bore such that the output member cooperates with an enlarged portion of the housing bore to define a plurality of pressure chambers. Slots on the input member and passages on the output member communicate the pressure source to one set of pressure chambers so that the increased pressure in these pressure chambers imparts rotation to the output member in response to rotation of the input member. A pair of cavities between the input and output members communicate the input member slots with the output member passages and projections on the output member oppose the slot side walls to limit rotation between the input member and output member.