A fluid leakage detection device includes: a rod seal provided in a cylinder head, a rod seal being configured to seal an annular gap between a piston rod and the cylinder head; a detection seal configured to seal an annular gap, a detection seal being configured to partition the detection space together with the rod seal; a communication passage in communication with the detection space; a pressure sensor configured to detect the pressure of the working oil guided through the communication passage; and a relief valve configured to release the pressure in the communication passage, wherein the detection seal is provided between the rod seal and a dust seal, the dust seal being configured to seal the annular gap by being provided in the cylinder head so as to face the outside of the cylinder tube.

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.

A wear ring for guidance of two machine components are arranged movably relative to one another along/around a movement axis, which is formed in one piece from a plastic or a reinforced plastic material and which is slit such that it has two free ends. The wear ring has a cross-sectional width W, which at least sectionally, increases in a radial direction towards the rear side of the wear ring. The wear ring has one or more recesses formed on its front side and/or on its the rear side for increasing its deformability and thus facilitate mounting thereof in a mounting groove of a machine element. Furthermore, a wear ring arrangement with a wear ring can be clipped into a mounting groove of one of the machine components of the wear ring arrangement.

A fluid leakage detection system has a detection space to which working oil leaked out through a rod seal is guided; the rod seal being configured to seal an annular gap between a piston rod and a cylinder head; a sensor unit configured to detect pressure in the detection space; and a controller configured to acquire detected result from the sensor unit, wherein the controller has: a calculation unit configured to calculate a pressure parameter representing a pressure fluctuation in the detection space; a determination unit configured to determine occurrence of leakage of the working oil based on the pressure parameter; and the pressure parameter includes an upper limit value and a lower limit value of the pressure fluctuation obtained from the detected result detected by the sensor unit within a predetermined detection period.

A manufacture configured to and process for inhibiting, from wear, a lock in a latching system comprising: a gland surrounding an actuator translating the lock through: a first fixed lock receptor and a moveable lock receptor. The manufacture and process include: inhibiting a skewing, of a lock central axis of the lock with the lock translating through the first opening and the opening in the moveable lock receptor, away from substantially aligning with: a first central axis of a first opening of the first fixed lock receptor, and an actuator central axis of the actuator, via fitting a first translation guide into the first fixed lock receptor. Also included is inhibiting: wear of a gland around an actuator in the lock while translating, and leaking, past the gland, of an actuator fluid within the lock; and skewing of an actuator central axis of the actuator.

A stability and control augmentation system (SCAS) actuator is operable for actuating a flight control surface of an aircraft. The SCAS actuator includes an actuator housing having a first aperture, a second aperture and a hydraulic chamber therebetween. A piston extends through the actuator housing. Fluid inlets are in fluid communication with regions of the hydraulic chamber. A first end portion of the piston is arranged to slide through the first aperture without a seal between the first end portion and the first aperture. A second end portion of the piston is arranged to slide through the second aperture without a seal between the second end portion and the second aperture. An intermediate portion of the piston is arranged to slide in the hydraulic chamber without a seal between the intermediate portion and the hydraulic chamber.

A pneumatic cylinder includes a cylinder body, a piston assembly, a connecting rod, and at least one pressure-relief valve. The cylinder body is formed with a cylinder chamber, and has an exterior disposed with at least one inlet-outlet passage and at least one pressure-relief opening, wherein the inlet-outlet passage is connected to the cylinder chamber. The piston assembly is contained within the cylinder chamber. The connecting rod is connected to the piston assembly, and protrudes out from the cylinder body. The pressure-relief valve is disposed in the pressure-relief opening, and has two ends connected to an outside of the pneumatic cylinder and the cylinder chamber respectively. When a gas pressure within the cylinder chamber is greater than a threshold value, the pressure-relief valve works to allow the cylinder chamber connecting to the outside for pressure relief.

A fixing device for fixing a second component part at a stationary first component part to be swivelable around a swiveling axis 2 having a cylinder that is displaceable transverse to the swiveling axis and filled with a fluid, a piston displaceably guided in the cylinder that divides the interior of the cylinder into a first working chamber and a second working chamber, with a first valve device that connects the first working chamber to the second working chamber when pressure in the first working chamber is higher than the pressure in the second working chamber, and a second valve device that connects the second working chamber to the first working chamber when pressure in the second working chamber is higher than the pressure in the first working chamber.

A piston rod and a rod cover which constitute this hydraulic cylinder are configured from aluminum or an aluminum alloy. An alumite coating film is formed on at least a part of the inner wall surface of the rod cover that constitutes a rod insertion hole, and a diamond-like carbon coating film is formed on the outer wall surface of the piston rod, said diamond-like carbon coating film being in sliding contact with the alumite coating film.

A fluid pressure actuator including a fluid pressure cylinder having a first position detector and a second position detector, a piston body having a piston head and a rod, the piston head mounted on the rod and slidably accommodated in the fluid pressure cylinder, the rod including a first scale and a second scale, the first scale facing the first position detector and the first position detector configured to detect a position in a sliding direction of the piston body, the second scale facing the second position detector and the second position detector configured to detect a position of the rod in a rotation direction of the piston body, and a controller configured to perform a first positioning control of a position of the rod in the sliding direction and a second positioning control of the rod in the rotation direction may be provided.