Abstract: Retraction of a landing gear assembly on an aircraft is actuated by a hydraulic actuator. The actuator includes a piston that travels within a cylinder along a stroke length between a first position corresponding to the landing gear assembly when extended and a second position corresponding to the landing gear assembly when retracted. The movement of the piston along its stroke length is snubbed at one end by a different amount according to the direction of travel, for example by use of an orifice plate that has a discharge coefficient that is greater in one direction than in the opposite direction. Asymmetric snubbing is thus provided, which enables the landing gear to retract faster.

Abstract: In accordance with the present invention an apparatus is provided to maintain separate upper and lower water levels in a bi-level tank. The purpose here is to maintain tank configurations for the water portion of an air/water pathway in the tank that will be followed by a buoyant power module during its electricity generating work cycle. During an operation, the module enters the tank and raises the lower water level. The apparatus is then expanded to displace a volume of water in the tank with a volume of air, which raises the upper water level. Subsequently, when the module leaves the tank, the upper water level is lowered. Further, the apparatus is collapsed to drop the lower water level back to its original level in the tank. Thus, the bi-level tank is reconfigured to receive another module, for another duty cycle.

Abstract: The present invention is an air shock absorber having a multiple stage design. The design includes a first algorithm for determining the compressed and extended lengths of the air shock based on the lengths of the parts for each stage. The first algorithm offers the air shock an extended length that is greater than twice its compressed length, an optimized extended length, and a construction capability based on adding stages. In particular, the extended length-compressed length relationship is a quality inherently unobtainable by current shock absorbers. The design also includes a second algorithm for determining the spring rate. The second algorithm offers the capability to both set-up the air shock with a relatively linear spring rate and make the relatively linear spring rate more linear.

Abstract: The subject matter of this specification can be embodied in, among other things, a linear actuator lock apparatus, including a housing having an inner surface defining an axial cavity including a first housing portion where the axial cavity has a first lateral size, a second housing portion where the axial cavity has a second lateral size that is larger than the first lateral size, and a face from the first housing portion to the second housing portion, a piston configured for axial movement within the axial cavity, a lock finger affixed to and extending away from the piston, where a finger end is configured to contact the face when extended and fit within the first housing portion when retracted, and a sleeve configured to move between a position in which the lock finger is permitted to extend and a position configured to contact and retract the lock finger.

Abstract: A dual piston valve actuator operable to provide an initial thrust force that is greater than a subsequent thrust force for moving a gate valve from a closed position to an open position. The actuator may include a first piston and a second piston movably disposed within a bore of the first piston. The first piston may define a first piston area for proving the initial thrust force, and the second piston may define a second piston area (that is less than the first piston area) for providing the subsequent thrust force. Movement of the first piston is limited relative to the second piston for moving the gate valve using the initial thrust force an initial portion of the valve stroke, while moving the gate valve using the subsequent thrust force the remaining portion of the valve stroke.

Abstract: An aircraft store ejector systems and subsystems thereof. Embodiments can include a two-reservoir re-pressurization system wherein a remote reservoir is used to maintain desired pressure in a local ejector reservoir. The system can include a release valve having a vent valve and valve piston. The release valve can control release of pressurized gas to a pitch control valve. The pitch control valve can be configured to distribute the pressurized gas between two or more ejector piston assemblies. One or more of the ejector piston assemblies can include multiple concentric piston stages and piston chambers, the piston chambers configured to contain a volume of gas. The ejector piston assemblies can be configured to compress the volume of gas within the piston chambers as the piston stages are extended out from the aircraft. Such compression can provide a return force to the piston stages.

Abstract: A piston pump dispenser in which a volume in a compartment defined inside a piston chamber-forming member and between axially spaced discs on a piston varies with movement of the piston in a cycle of operation due to the piston having a tubular portion between the discs which varies in axial length. The tubular portion has a circumferentially extending wall in the shape of a solid of revolution about an axis of the piston with opening through the wall for fluid flow. The tubular portion acts as a spring to axially bias the axially spaced disc apart.

Abstract: The catheter device comprises a drive shaft connected to a motor, and a rotor mounted on the drive shaft at the distal end section. The rotor has a frame structure which is formed by a screw-like boundary frame and rotor struts extending radially inwards from the boundary frame. The rotor struts are fastened to the drive shaft by their ends opposite the boundary frame. Between the boundary frame and the drive shaft extends an elastic covering. The frame structure is made of an elastic material such that, after forced compression, the rotor unfolds automatically.

Abstract: A driving device for pivoting a flap with respect to a body includes a cylindrical pressure tube having a closed first end and a second end with a seal, a piston dividing the pressure tube into a first working chamber and a second working chamber, a piston rod extending through the first working chamber and the seal, a gas under pressure in the first and second working chambers, and a sealing and guiding cap fixed to the second end of the pressure tube. An outer tube has a closed first end and an open second end which receives the pressure tube in a telescoping manner, thereby forming a third working chamber between the second end of the pressure tube and the first end of the outer tube, wherein a fluid can be conveyed into and out of the third working chamber.

Abstract: A steam turbine engine that converts highly compressed steam to mechanical rotatative torque. An upper sealing gate and lower sealing gate alternately open and block the intake port and exhaust port accordingly through the use of a lever arm and cam and pulley system.

Abstract: A hydraulic support element having a housing, a pressure piston, a high pressure chamber for a hydraulic means extending between a bottom face of the pressure piston and a bottom of the housing, wherein the housing includes a passage for the hydraulic means, which communicates radially inwardly with an aperture in the pressure piston, wherein the pressure piston includes a deflecting sheath for the hydraulic means, tightly contacting the pressure piston at the interior jacket axially below the aperture and extending to the proximity of a head of the pressure piston, wherein a rising line for the hydraulic means is formed between the deflecting sheath and the interior jacket, which starts at the aperture and leads in the area of the head into a reservoir inside the deflecting sheath directly in front of the return valve and with the deflecting sheath having at least one perforation axially above its contact.

Abstract: An integrated breakaway cylinder for controlling a boom of a self-propelled sprayer and method for constructing a boom assembly is disclosed in the present application. The integrated breakaway cylinder is constructed from a first stage cylinder and a second stage cylinder. The first stage cylinder is configured in a rod and barrel arrangement. The second stage cylinder is also configured in a rod and barrel arrangement, with the barrel of the first stage cylinder serving as the rod of the second stage cylinder. The first stage cylinder operates to extend and retract a boom. The second stage cylinder operates to absorb shock from inertia or the boom impacting an object. The design of various embodiments of the present invention couples the operation of maneuvering a boom with shock absorption into a single integrated cylinder.

Abstract: A low-temperature-fluid storage tank capable of efficiently increasing the pressure of fluid without heating the fluid is provided. There is provided a booster pump which includes a piston having a piston head and a piston rod and a cylinder having a compression chamber that accommodates the piston head so that a fluid is compressed by one end surface of the piston head. The piston head is provided with a bellows for separating a space adjacent to the piston rod from a space adjacent to the cylinder in the compression chamber.

Abstract: A hydraulic motor with rotating shaft coupled to a piston with alternating rectilinear displacement. The hydraulic motor comprises a casing enclosing a rotating shaft, a piston and an inverter comprising a first sleeve formed as one piece with the piston, a second sleeve, fixed in position, and a distributor mounted so as to rotate in the interior of the second sleeve and conduit and hole elements arranged between the second sleeve and the distributor and means for controlling the rotation of the distributor as a function of the displacement of the first sleeve so as to invert the direction of displacement of the piston.

Abstract: Actuators, and corresponding methods and systems for controlling such actuators, provide independent lift and timing control with minimum energy consumption. In an exemplary embodiment, an actuation cylinder in a housing defines a longitudinal axis and having first and second ends in first and second directions. An actuation piston in the cylinder, with first and second surfaces, is moveable along the longitudinal axis. First and second actuation springs bias the actuation piston in the first and second directions, respectively. A first fluid space is defined by the first end of the actuation cylinder and the first surface of the actuation piston, and a second fluid space is defined by the second end of the actuation cylinder and the second surface of the actuation piston. A fluid bypass short-circuits the first and second fluid spaces when the actuation piston is not substantially proximate to either the first or second end of the actuation cylinder.

Abstract: An integrated hydraulic valve actuator for use in a camless internal combustion engine. The valve actuator includes a separate bolt-on housing defining a through opening receiving a cylindrical liner. The liner internally defines an internal cylinder providing a riding surface, which coaxially surrounds an outer surface of a tubular boost piston. The boost piston defines an inner cylinder, which provides a riding surface for a drive piston fitted within the inner cylinder of the boost piston. The pistons are axially reciprocable within the liner cylinder. A piston position sensor extends radially into the housing and engages a cam on the drive piston to relay the position of the drive piston to a controller. The actuator is preassembled and the housing is attached to an engine cylinder head or cylinder head supply manifold to operate an associated exhaust or intake valve.

Abstract: A telescopic cylinder comprised of an outer cylinder, a plurality of decreasing diameter piston/sleeve assemblies concentrically mounted in the outer cylinder for reciprocal axial movement relative thereto, and a plunger assembly concentrically mounted within the innermost one of the piston/sleeve assemblies for reciprocal axial movement relative thereto. The piston/sleeve and plunger assemblies having a piston with at least one lateral hole and at least one lateral passage, respectively, extending into its interior, and in fluid communication with a passage in the outer cylinder for receiving pressurized fluid. Each lateral hole having an orifice surface located at the radially outermost portion of the hole and having a diametral dimension no smaller than the maximum diametral dimension of the hole. Each piston further having at least one longitudinally relieved portion located on its outer circumferential surface extending from a first end towards a second end.

Abstract: A hydraulic cylinder (10), especially as a pit prop or moving cylinder unit in underground mining, with a locking ring (16) arranged on an outer cylinder tube (11) sealing it at its end with a lead through for an axially movable rod element (12; 13) accommodated in it. The locking ring (16) is provided in the lead through surrounding the rod element (12; 13) with a sealing arrangement (22) resting on the outer side (34) of the rod element (12; 13). The sealing arrangement (22) has a guide ring (29) provided with grease grooves (33) open to the outer side (34) of the rod element (12, 13), which can, be supplied with lubricant for the grease grooves (33) via a lubricant line (35) accessible on the outside on the hydraulic cylinder (10) and which is arranged in an accepting groove (40) formed interlocking ring (16) between an axially inner and an axially outer collar (38; 39).

Abstract: A semi-levered landing gear includes a main strut, a wheel truck pivotally attached at a main pivot to a lower end of the main strut and supporting forward and aft wheels, and an auxiliary strut attached at its upper end to the main strut and at its lower end to the wheel truck forward of the main pivot. The auxiliary strut includes a main piston that slides within a cylinder barrel and is attached at its lower end to the auxiliary pivot, and a floating piston that slides relative to the cylinder barrel and the main piston and divides the cylinder barrel into a pair of fluid chambers. The main piston includes snubbing holes or orifices through which fluid can flow between the two fluid chambers.

Abstract: A hydraulic lifting-lowering-system for a working table, a couch or lying furniture or another heavy object allows the height level or position to be frequently adjusted or changed. The system includes a predetermined amount of hydraulic fluid, a hydraulic fluid accumulator, the fluid pressure of which on the hydraulic fluid side is adjustable, a single acting hydraulic cylinder with two end caps, a piston pressure chamber and a piston rod which, via a piston rod sealing ring, extends sealingly out through the one end cap of the cylinder. The piston pressure chamber is pressure fluid connected to the hydraulic fluid side of the accumulator. The hydraulic cylinder is of the plunger piston type, and the cylindric tube of the hydraulic cylinder is slideably and telescopically mounted in a cylindrical guiding tube, which surrounds the piston rod in its entire length and is rigidly secured to the one end of the piston rod via a cross plate or similar construction part.

Abstract: The inside of a cylinder is divided into front and rear cylinder chambers, a primary-side piston and a secondary-side piston, each formed by an annular disc part and an annular tube part are fitted into each cylinder chamber, with the annular tube parts of each loosely fitted together, and the secondary-side piston surrounding an operating piston rod so as to hold the operating piston and being fit into the operating piston. The first front cylinder chamber and the second rear cylinder chamber defined by the primary- and secondary-side pistons are connected by a communicating passageway with a relief valve inserted therein, this relief valve being switched to the open condition by either a prescribed pressure or a valve opening/closing bar that is provided upright on the primary-side piston.

Abstract: A hydraulic drive cylinder with a cylinder tube, which at its respective ends has a cylinder base and a cylinder head, thus delimiting a cylinder space. A piston can move to and fro in the cylinder space between the cylinder base and the cylinder head, which piston delimits a head-side chamber and a base-side chamber, which chambers are sealed off from one another by the piston. The piston rod has a free end which is delimited by an end face, which end face is situated in the head-side chamber. At the said free end, the piston rod is provided with a first stop.

Abstract: A hydraulic tile and trim mechanism for a marine outboard drive that provides a compact assembly and which ensures that contaminants which may enter the hydraulic fluid can accumulate in the fluid reservoir and will not be circulated by the fluid pump. This is accomplished by positioning the reservoir below the fluid pump and using a pick-up tube that does not extend into the bottom of the reservoir so that the contaminants can accumulate therein without being circulated.

Abstract: A pneumatic motor including a motor body having a piston chamber with opposed chamber ends, at least two valve chambers, an inlet for flowing a pressurized fluid into the piston chamber and each of the at least two valve chambers, a number of outlets provided in the housing for exhausting the pressurized fluid from the piston chamber and each of the at least two valve chambers. The motor also includes a three-way valve member adapted to be located in each of the at least two valve chambers, the valve members each have at least one open end and at least one port formed along the valve member body. A spool member is located in one of the valve chambers, each spool member has a first end adapted to be located in the open end of the valve member.

Abstract: A telescoping fluid actuator assembly including a housing having a plurality of concentrically disposed fluid actuators disposed therein. Each fluid actuator includes a cylindrical housing enclosing a piston and piston rod. Fluid passage means is provided for alternately directing fluid pressure to the front and back piston faces of each piston to effect forward and rearward movement of the pistons and the associated piston rod. The innermost concentric fluid actuator has a piston rod extending from the housing for engaging a workpiece for movement thereof. All of the concentrically mounted fluid actuators, except the innermost fluid actuator, is provided with a hollow piston rod which forms the cylinder housing for adjacent concentric fluid actuators.

Abstract: A fluid operated cylinder device particularly adapted to lift a load relative to a load support includes a hollow casing having a closed end for attachment to the load support; an elongated rigid rod extending lengthwise of the casing and having a first end arranged within the casing and rigidly fixed to its closed end and a second end disposed outwardly of the casing for attachment to the load support; at least one open ended fluid operated cylinder arranged intermediate the casing and rod for sliding movements lengthwise thereof, such cylinder having an outer end disposed outwardly of the casing for attachment to the load; and fluid means for introducing and withdrawing fluid from the casing for effecting sliding movements of the cylinder and lifting and lowering of the load. Single and double acting embodiments of the cylinder device are disclosed.

Abstract: A pneumatic actuator for deploying flexible bodies and the like is disclosed. The actuator is a plurality of telescoping tubes made of high temperature resistant graphite material which are extended by the pressure of gases produced internally by a gas generator contained within the innermost tube. The extended tubes are locked in position automatically and venting of the gases from the tube interior is provided for simultaneously with full and locked extension of the tubes.

Abstract: A double acting telescopic hydraulic cylinder comprises a hollow base member arranged to be supported pivotally and including a removably end closure at its inner end. The interior surface of the base member incorporates a set of machined grooves which removably mount a set of rings that act as a stop, a fluid seal, a bearing and a wiper for the largest of a plurality of telescoping cylinder stages each incorporating a similar set of internal machined grooves and rings which cooperate with the adjacent smaller stage. The smallest telescopic cylinder stage receives a hollow telescopic piston stage closed at its inner and outer ends. An internal groove on the inner end of each telescoping cylinder stage removably mounts a lifting ring for engaging the next smaller stage. An external groove on the inner end of each stage removably mounts a guide bearing ring for cooperation at its forward end with the stop ring of the adjacent larger stage.

Abstract: A hydraulic ram for use in thrust-jacking of tunnel linings comprises a cylindrical outer member, a cylindrical inner member reciprocable within the outer member, and an extension member reciprocable within the inner member. A two-part clamping ring is provided for releasably locking the extension member to the inner member. An auxiliary drive is provided for retracting the extension member rapidly within the inner member. The auxiliary drive may be a mechanical spindle drive, or a hydraulic drive having an auxiliary piston reciprocable within an axial bore formed in the extension member. The clamping ring comprises spring means for urging the parts of the clamping ring in to the closed position, and piston-and-cylinder means for urging the parts of the clamping ring apart, against the biasing force of the spring means, to open the clamping ring.

Abstract: A hydraulic system having a single acting, mult-stage, synchronous hydraulic jack having a trapped oil space which provides the required synchronism. The hydraulic system additionally includes a first external pump in fluid flow communication with an oil space disposed between the outer cylinder and an intermediate section, and a second external pump disposed in fluid flow communication with the trapped oil space between the intermediate section and an inner plunger section. Oil leakage from the trapped oil space is detected when the sections are retracted. The next time the sections are to be extended following such detection, both pumps are automatically started, with the second pump being deactivated when the trapped oil space has been replenished.