An aircraft thermal hydraulic active-warming system includes an active thermal-warming valve interoperably coupled between a hydraulic pressure line and a hydraulic low-pressure return line and a hydraulic actuator arranged in parallel with the active thermal-warming valve between the hydraulic pressure line and the hydraulic low-pressure return line.

A self-rotation graphene heat-dissipation device for a direct-drive electro-hydrostatic actuator, that includes inner and outer walls of a shell eccentrically arranged relative to each other, the shell sleeves on an outer side of a self-rotation mechanism. The self-rotation mechanism is arranged on an outer side of a shaft; the shaft is coaxial with the inner wall of the shell and connected with outer and inner end covers. The self-rotation mechanism includes a rotor and blades, the rotor sleeves on the shaft and is connected with the outer and inner end covers. The rotor is slidably connected with the blades, and outer walls of the blades are closely attached to the inner wall of the shell. Graphene heat-dissipation layers are coated on outer walls of all of the shell, blades, the rotor, the inner and outer end covers respectively.

A pressure regulator for an x-ray apparatus includes a piston housing having a recess formed therein and a piston seated in the recess. The piston is free to reciprocate, and define a variable volume chamber, within the recess. A circumferential groove is formed in an exterior surface of the piston, and a seal is seated in the circumferential groove. A manifold in the piston housing places the chamber in fluid communication with an exterior of the piston housing.

Actuator systems and methods of operation are disclosed. The systems include a hydraulic actuator having a primary piston having a piston head arranged within a housing defining retract and extend chambers on opposite sides of the piston head. A control element is configured to control a supply of pressure to each of the retract and extend chambers. An actuator valve is coupled to the housing and includes a secondary piston that is biased into the retract chamber in an open flow state and when the primary piston is in a fully retracted state the piston head urges the secondary piston into a closed flow state. The actuator valve defines a flow chamber where, in an open flow state, fluid can be passed through the flow chamber and in a closed flow state the fluid is prevented from passing through the flow chamber.

An actuator is provided. The actuator includes a first body defining an interior, a second body disposed about the first body and defining space between an exterior of the first body and an interior of the second body, a plunger including a head sealably disposed in the interior and a rod connected to the head and sealably extended through the first and second bodies and first and second fluid systems. The first fluid system is insulated from the space. A first fluid is moved relative to the interior for causing the plunger to extend or retract by way of the first fluid system. A second fluid is moved through the space by way of the second fluid system.

The present patent of invention relates to a hydraulic unit (U) with a pneumatic cylinder (15) that works jointly with a servomotor (M), together with a ball screw (29) to together move a hydraulic piston pump (8), made up of a hydraulic plunger (7), with related sealing elements to prevent oil leaks, noise, metal-on-metal attrition and loss of efficiency, that is moved upwards and downwards using a ball screw (29) and a pneumatic cylinder (15), jointly with a servomotor (M) which, when moved, pushes the pressurized oil outwards while filling the opposite hydraulic chamber with an oil suction movement, the pumped oil entering a hydraulic pressure accumulator (25), where it remains idle to be used when required and being supplied by the up/down movement of the piston, generating continuous pumping, which is automatically stopped when the hydraulic pressure accumulator (25) is full and has reached the predetermined hydraulic pressure.

An actuator includes a housing, a first chamber inside the housing, a cylinder within the housing, and a second chamber within the housing. The cylinder fluidically isolates the first chamber from the second chamber. The actuator also includes a rod connected to the cylinder and extending through the second chamber and the housing. A shell is spaced apart from the housing and defines a fluid gap between the shell and the housing. The shell includes a shell inlet fluidically connected to the fluid gap and a shell outlet fluidically connected to the fluid gap.

A fluid control apparatus includes: a metal plate; a heater configured to heat the metal plate; a first joint block and a second joint block provided on an installation surface of the metal plate, extending in a predetermined direction, and formed with a flow passage therein; a first pipe extending along the predetermined direction between the first joint block and the second joint block; a heat transfer cover provided on the installation surface of the metal plate; and a first fluid control device mounted to the first joint block and the second joint block so as to straddle over the first pipe. The heat transfer cover has a rectangular cross-sectional shape, extends along the predetermined direction, and includes a first cover member and a second cover member mounted around an outer circumference of the first pipe in contact with each other. The first cover member covers a part in a cross section of the first pipe and has a first abutment surface abutting on the installation surface of the metal plate. The second cover member covers another part in a cross section of the first pipe and has a second abutment surface abutting on the first fluid control device.

A working medium circuit for a hydrodynamic machine. The working medium circuit includes a working medium container, an inflow line, an emptying line, and a heat exchanger. The working medium can be moved out of the working medium container into the working chamber for a first operating state, in particular the braking mode, and the working medium can be moved out of the working chamber back into the working medium container for a second operating state, in particular the non-braking mode. For aerating and ventilating, the working chamber is connected at least indirectly via a ventilating line to a chamber which has a ventilating device with respect to the surroundings and in which working medium can collect.

A system uses a two-stage electrohydraulic servo valve that includes an additional control port that commands a fail-fixed valve to lock the position of a device in the last commanded position. The additional port is modulated by an existing land on the EHSV valve element, adding little to no complexity. Major technical benefits of the disclosed system are that it adds little to no cost, complexity, size, or weight the device being controlled. The disclosed configuration allows for the use of a relatively small and simple fail-fixed valve, and the control ports on the controlled device keep “drift” to a minimum, when transitioning between normal operating mode and fail-fixed operating mode.