Abstract: Systems and methods for recovering power fluid used to power a device under water and for pumping the recovered power fluid to a fluid container above a surface of the water, the method in certain aspects including: flowing fluid from a subsurface apparatus to a subsurface recovery system, the fluid initially provided to the subsurface apparatus to power the subsurface apparatus; and the subsurface recovery system including a pump system for selectively pumping recovered power fluid to a fluid container above a surface of the water, the pump system having at least one pump and, in some aspects, a first pump, a second pump, and a valve system; the valve system controlling the first pump and the second pump to allow only one pump of the first pump and the second pump to pump recovered power fluid to the fluid container above the surface of the water; and pumping recovered power fluid to the fluid container with only one pump at a time.

Abstract: A marine vessel control apparatus is arranged to start and stop engines that are respectively provided in multiple propulsion devices. The marine vessel control apparatus includes multiple individual start/stop switches arranged to correspond to the respective multiple propulsion devices and arranged to be operated by an operator to individually start and stop the engines in the respective multiple propulsion devices, an all-device start/stop switch arranged to be operated by the operator to collectively start and stop the engines in the multiple propulsion devices, an operating state acquiring unit arranged to acquire operating states of the engines in the respective multiple propulsion devices, and a control unit. The control unit includes multiple input ports corresponding to the respective multiple individual start/stop switches. Each of the input ports is connected with the corresponding individual start/stop switch. All of the input ports are connected commonly with the all-device start/stop switch.

Abstract: The invention relates to a percussion device comprising two percussion pistons alternately making a percussion motion and a control valve for controlling the percussion pistons. The control valve (7) comprises a slide (8) affected by a force so that the slide is generally in a first position, but moves at the end of the percussion motion of the first percussion piston from the first position to a second position and correspondingly back to the first position at the end of the percussion motion of the second percussion piston (4).

Abstract: A pump having both a short stroke pumping mode and a long stroke pumping mode. The pump has two material cylinders, each with an attached hydraulic cylinder for operating a piston rod extending through both the material and hydraulic cylinders. The piston rods are driven by hydraulic fluid supplied to the hydraulic cylinders and are synchronized so that as one piston rod extends, the other piston rod retracts. The piston rods draw material into the material cylinders when retracting, and pump material out of the material cylinders when extending. To pump in a short stroke mode, a diverter valve is placed between the hydraulic pump and the hydraulic cylinders which diverts an amount of hydraulic fluid to the cylinders, causing the hydraulic pistons to only be extended about half the length of the hydraulic cylinder.

Abstract: A telescopic boom with a multistage, lockable hydraulic cylinder is provided with a protection against lateral buckling of the hydraulic cylinder, said hydraulic cylinder being supported by the more rigid boom members (telemembers). For this purpose, a multipart supporting device is provided, one part of said supporting device being secured to at least one unit of the multistage hydraulic cylinder and the other part thereof being secured to the inner wall of the at least one telemember. The two parts of the supporting device are continuously in engagement with one another so that the desired protection against buckling of the hydraulic cylinder will be guaranteed at all positions of the boom. Furthermore, suitable measures guarantee that, starting with the cylinder unit having the largest cross-section, it is always the cylinder unit having the next smaller cross-section which, in an orderly sequence, is first fully extended, the reverse order being observed during the retraction process.

Abstract: A pair of control valve assemblies for alternately actuating a pair of fluid-driven free-piston devices by using fluid pressure communication therebetween. Each control valve assembly is switched by a pressure signal depending on the state of its counterpart's piston. The communication logic is arranged to provide overlap of the forward strokes of the pistons, so that at least one of the pair will always be pressurized. Thus, uninterrupted pumping of liquid is made possible from a pair of free-piston pumps. In addition, the speed and frequency of piston stroking is entirely dependent on the mechanical power load applied. In the case of a pair of pumps, this enables liquid delivery at a substantially constant pressure over the full range of flow rates, from zero to maximum flow. Each of the valve assemblies uses an intake-exhaust valve and a signal valve with the signal valve of one pump being connected to be pressure responsive to the piston of the opposite cylinder or pump.

Abstract: A control valve assembly for alternately actuating a pair of fluid-driven free-piston devices by using fluid pressure communication therebetween. Each control valve is switched by a pressure signal depending on the state of its counterpart's piston. The communication logic is arranged to provide overlap of the forward strokes of the pistons, so that at least one of the pair will always be pressurized. Thus, uninterrupted pumping of liquid is made possible from a pair of free-piston pumps. In addition, the speed and frequency of piston stroking is entirely dependent on the mechanical power load applied. In the case of a pair of pumps, this enables liquid delivery at a substantially constant pressure over the full range of flow rates, from zero to maximum flow.

Abstract: A quick acting diversion valve can be constructed so that a pressure difference between the sides of a bistable diaphragm can be used to cause the diaphragm to change in configuration so as to move a valve body in a housing in order to change the manner in which passages or ports in the housing are connected.

Abstract: For the production and exact control and regulation of very high pressures, in particular for actuating a press, two pressure intensifiers are provided which each have a differential piston. The second pressure intensifier is connected via a shutoff valve to the first pressure intensifier and to the load or consumer. Both pressure intensifiers have a small volume compared with the volume required by the consumer. By activating the second pressure intensifier fluid can be exchanged between the consumer and the first pressure intensifier to replenish the first pressure intensifer in a pressure buildup phase and to empty the first pressure intensifier in a pressure relief phase.

Abstract: An indexing mechanism comprising a member adapted to be advanced a predetermined amount and along a predetermined path, a pair of spaced drivers, and a control valve for operating the drivers in an alternative manner. The member adapted to be advanced defines a profile surface including a plurality of spaced radial segments. Each radial segment includes a crown section which is joined to an adjacent crown section by two oppositely directed ramps defining a fillet radius therebetween. The spacing between the drivers being such that when one driver is urged against a crown section the other driver acts against a fillet radius. The drivers are operated by the control valve 180.degree. out of phase relative to each other. A driver, after moving off a crown section, coacts with ramp to impart a driving force to the member. The driving force being sufficient to move the member in an indexed fashion the predetermined amount of its movement.

Abstract: A feedback type of diversion valve which can be used to sequentially "operate" or "activate" fluid responive structures such as tubes of a pillow.

Abstract: A hydraulically actuated multi-cylinder reciprocating piston pump includes two double acting cylinder and piston type hydraulic actuators each connected to a working fluid piston and hydraulically interconnected by a control circuit to provide alternate delivery and suction strokes to the respective working fluid pistons. The piston rod chambers of the hydraulic power actuators are interconnected to transfer operating fluid therebetween to drive the actuating pistons on their return strokes. Each cylinder actuator is provided with a sleeve type pilot valve interposed in a hydraulic circuit including a main spool type control or distributing valve for operating the cylinder actuators in timed relation to each other. The hydraulic circuit includes a main high pressure source of actuator operating fluid and a lower pressure source of pilot actuator and leakage make up fluid for the actuator piston transfer circuit.

Abstract: A pilot assembly for switching the fluid supply valve of a hydraulic pump is actuated by the pressurized hydraulic fluid which operates the hydraulic pump. The hydraulic pump includes a main cylinder, a main piston within the main cylinder, and a main valve for supplying pressurized hydraulic fluid to the rear end of the main cylinder for driving the piston forwardly. The pilot assembly includes a pilot cylinder and a pilot spool within the cylinder. A first hydraulic conduit connects one end of the pilot cylinder to the front end of the main cylinder, and a second hydraulic conduit connects the other end of the pilot cylinder to the main cylinder at a position spaced rearwardly from the front end of the main cylinder. When the main piston passes forwardly of the second hydraulic conduit, the pressurized hydraulic fluid in the main cylinder moves the pilot spool, and pressurized hydraulic fluid is allowed to flow to the main valve to switch the main valve.