A mobile apparatus with a fluid pressure-operated implement mounted at a distal end of a boom includes a connection apparatus for selectively rotating the implement about an actuator axis at the distal end of the boom. The connection apparatus includes a rotary actuator and a pressurized fluid circuit for delivery of pressurized fluid through the rotary actuator to the implement. The pressurized fluid circuit includes channels establishing a fluidic connection axially through the rotating shaft of the rotary actuator. The pressurized fluid circuit facilitates passage of pressurized fluid through an internal, protected environment to the implement.

An artificial lift system can include an actuator operable to reciprocate a rod string in the well, the actuator including a piston reciprocably disposed in a cylinder, and a piston rod connected to the piston, and a rod rotator that continuously rotates the piston rod relative to the cylinder as the piston displaces in a longitudinal direction relative to the cylinder. A method of rotating a rod string can include connecting the rod string to a piston rod of an actuator, longitudinally reciprocating the piston rod relative to a cylinder of the actuator and a mandrel of a rod rotator, and rotating the piston rod relative to the mandrel in response to the reciprocating, the mandrel being disposed at least partially within the piston rod during the rotating. A rod rotator can include a mandrel having a helical external profile configured to attached to a cylinder of a hydraulic actuator, an internal profile complementarily shaped relative to the external profile, and a one-way clutch.

In a rotary actuator comprising a housing containing a piston and having a cover and a base, thread-like guide grooves in the piston, a shaft having a transverse axis and being rotatable about an axis of the rotary actuator which transverse axis engages into the guide grooves, and torque support engaging into guides in the piston, which torque supports are anchored in the housing, wherein the transverse axis on both ends comprises bushes contacting raceways of the guide grooves, each bush is cambered and each raceway is configured with an undercut corresponding to the cambering.

Actuators and devices are provided for imparting a rotary movement and comprising in a longitudinal direction first and second hydraulic cylinders, characterised in that the first driver is a linear hydraulic cylinder comprising a first piston, and that the second driver is a linear hydraulic cylinder comprising a second piston, and in that the devices include a member for converting linear motion into rotary motion in order to convert a translation movement of the second piston into a rotary movement.

A rotary joint, including: a hydraulic follow-up mechanism and a rotary transmission mechanism. The hydraulic follow-up mechanism includes a cylinder body, a valve sleeve, a valve core, a valve body, a left end cover and a right end cover. The rotary transmission mechanism includes a tray, a stabilizing ring, a follow-up disk, a torque transfer disk and a stable supporting wheel mechanism. The left end cover and the right end cover are arranged at the left and right ends of the cylinder body, respectively. The valve body is concentrically mounted in a cylindrical hollow chamber of the cylinder body. The output shaft at the right end of the valve body projects out of the right end cover. The right end of the valve core is provided with a valve core torque transfer shaft extending rightwards through the right end of the valve body.

A rotary actuator where a thrust bearing ring is positioned at an inside of a tube assembly accommodating oil, thereby reducing abrasion and damage caused by rolling friction and improving rotary power of an axle load by increasing hydraulic pressure of a piston. The rotary actuator includes the tube assembly, a piston, an axle load assembly, and a thrust bearing ring. The tube assembly is provided with a tube spiral portion where a spiral is formed at an inner circumference surface, and is formed of a first passage where oil flows into and out and a second passage spaced apart from the first passage by a fixed distance.

The invention relates to a quick-change device (IO) having at least one locking bolt (26) and a motor drive which moves the locking bolt (26) into a locking position and an unlocking position, wherein the drive (16) has an energy connection (28a, 28b) and output means (34) interacting with the locking bolt (26), wherein the drive (16) comprises a rotary drive (30) having a motor and an output shaft (34), wherein the output shaft (34) is mechanically connected to the locking bolt (26), with the result that the locking bolt (26) is movable along an actuation axis. The invention is distinguished by the fact that the drive (16) has an attachment (20) for a shaft-hub connection, on which attachment a tool for manual actuation can be mounted, with the result that a manual actuation acts directly on the output shaft (34) and here the attachment (20) is arranged coaxially to a rotary connection (32a, 32b) of a gear shaft (32c, 32d).

A modular motor is disclosed that includes a piston/harmonic drive assembly that is axially cycled. The piston/harmonic drive assembly is coupled to a ball transfer arrangement that converts the axial motion into rotary motion to rotate a rotor that can be used to rotate a drill bit.

A hydraulic swivel drive for a grab that has two gripping arms or shells movable like tongs, including two swivel shafts parallel to each other and rotatably mounted in a drive housing, whose shaft ends are connectable with the gripper arms or shells, wherein the swivel shafts each have two oppositely threaded screw engagement portions, with which two pistons movable in opposite directions by means of hydraulic pressure for driving the swivel shafts are in screw engagement. Two differently large and differently contoured cylinder pressure chambers can be assigned to each piston in order to optimally adapt the cross-sectional area of the pistons for each of the reciprocating positioning movements and to appropriately select the pressure conditions. To be able to run in the differently contoured and dimensioned cylinder pressure chambers, each of the pistons is provided with different piston portions which are adapted to the respective cylinder pressure chamber.

A hydraulic actuator employing, in part, a short piston stroke distance and a planet gear amplification to achieve a relatively rapid actuation through a relatively low power input.