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.

A locking mechanism comprises a piston element comprising a piston groove extending in an axial direction along a radially outer surface of the piston element, a housing comprising a bore for receiving the piston element for reciprocating axial movement between a locked position and an unlocked position, a locking ball received in the piston groove and a locking ring mounted for rotational movement about the piston element between a locking position and an unlocking position, the locking ring comprising a radially inner locking ring groove, the locking ring groove having a recess formed in a radially inner surface thereof for receiving the locking ball in the unlocking position of the locking ring. The piston groove comprises a first axially extending section and a second axially extending section, the radial depth (D1) of the first axially extending section being greater than the radial depth (D2) of the second axially extending section.

An agricultural system that includes a cylinder and a rod that moves axially in and out of the cylinder to raise and lower a header. A cylinder lock system controls movement of the rod. The cylinder lock system includes a cap-end fixture that couples to the cylinder and receives the rod. A rod-end fixture couples to an end of the rod. The system includes a lock piston. The lock piston includes a protrusion. The lock piston rotates about the rod and selectively couples the protrusion to the cap-end fixture to lock and unlock the rod-end fixture to the cap-end fixture.

A gas lift for preventing sagging may include in the gas lift comprising a tube and a rod slidably installed inside the tube, and filled with gas inside the tube, a moving member for moving with the rod when the rod slides at one side of the portion received inside the tube of the rod, a first stopping part coupled to the moving member and for stopping sliding of the moving member primarily in the tube, and a second stopping part coupled to the moving member and for stopping sliding of the moving member after the moving member and the first stopping part have been coupled to each other.

The invention relates to a locking unit, in particular for the parking lock of an automatic transmission, for locking the movement of a piston which is movable by a drive and in particular can be acted upon with pressure or hydraulic pressure, wherein the piston is at least partially mounted in a center section which is at least partially surrounded by a housing.

The invention relates to an actuation device (22) for a system (20) including an emergency ram air turbine (21). Said device includes a ram (22) extending along a longitudinal axis (29) and including: a cylinder (30) configured to be connected to an aircraft structure (23) and a piston (33) extending into the cylinder (30) and defining two chambers (31, 32) in the latter. The piston (33) is equipped with a rod (33a) partially extending outside the cylinder (30). Said rod portion extending outside the cylinder (30) is configured to be connected to the emergency ram air turbine (21). The piston (33) is configured to move, relative to the cylinder (30), between a retracted position and a released position, wherein the length of the portion (33b) of the rod (33a) extending outside the cylinder (30) is greater than in the retracted position. One (31) of the chambers of the cylinder (30) is equipped with at least one gas generator (34) configured, when the piston (33) is in the retracted position, to release gases into said chamber (31) so that the piston (33) moves, in the cylinder (30), from the retracted position to the released position as a result of a difference in pressure between the two chambers (31, 32) of the cylinder (30).

An apparatus for unlocking an actuator, such as a RAT actuator includes a first member; and a second member movable between a blocking position in which said second member is engaged with said first member so as to block movement of said first member and an unblocking position in which said second member is disengaged from said first member so that movement of the first member is not blocked. The first member is an arm arranged such that in the blocking position it is disposed between said second member and a lock release element of said actuator.

A level control system for a vehicle, in particular a rail vehicle, includes at least one level control cylinder and one level control piston, the level control piston being movably guided in the level control cylinder in order to adjust the level of the rail vehicle, the level control piston having an outer piston sleeve and a piston main body at least partially accommodated in the piston sleeve, and the piston main body being slidable relative to the piston sleeve for wear readjustment and being lockable and/or fixable in at least two adjustment positions.

An actuator in which the abrasion of a piston and a cylinder can be prevented and it is difficult for the smooth movement of the piston to be hindered is provided. The actuator includes a cylinder (51), a piston (52) that moves inside the cylinder (51) according to a supplied fluid pressure, and a detent mechanism (54) that fixes a position of the piston (52) until the fluid pressure exceeds a predetermined value. The detent mechanism (54) includes a first elastic member 54a and a second elastic member 54b which are arranged to face each other with an axis (a) of the piston (52) interposed therebetween and press the piston (52) so as to sandwich the piston (52) therebetween.

A lockable actuator includes: a body; a screw for pivoting relative to the body; a nut engaged on the screw so as to move along the screw between an over-retracted first position and a deployed second position on opposite sides of a retracted third position; a sleeve constrained to rotate with the screw and slidably mounted thereon in order to be moved by the nut; and an obstacle secured to the sleeve and a pawl capable of passing collectively between an active state and an inactive state, the pawl and the obstacle being arranged in such a manner that the pawl in its active state can co-operate with the obstacle only after the nut has been moved through a predetermined distance from its third position towards its second position.