An axial, through-shaft actuator that is particularly useful for a variably actuatable water pump having a pump chamber, with an inlet and an outlet is provided. A hollow drive shaft extends into the pump chamber. A drive wheel is connected to the drive shaft. A variable flow impeller assembly having an impeller part connected to the drive shaft and a cover part, which is axially movable relative to the impeller part is located in the pump chamber and is movable from a first, pumping position to a second position to prevent pumping. A cup actuator assembly is axially movable on the hollow drive shaft, and includes an actuator plate and a pin extending through the hollow drive shaft that connects the axially movable impeller part and the actuator plate. An actuator displaces the actuator plate in the axial direction of the drive shaft to move the axially movable part.

An axial, through-shaft actuator that is particularly useful for a variably actuatable water pump having a pump chamber, with an inlet and an outlet is provided. A hollow drive shaft extends into the pump chamber. A drive wheel is connected to the drive shaft. A variable flow impeller assembly having an impeller part connected to the drive shaft and a cover part, which is axially movable relative to the impeller part is located in the pump chamber and is movable from a first, pumping position to a second position to prevent pumping. A cup actuator assembly is axially movable on the hollow drive shaft, and includes an actuator plate and a pin extending through the hollow drive shaft that connects the axially movable impeller part and the actuator plate. An actuator displaces the actuator plate in the axial direction of the drive shaft to move the axially movable part.

An adjustable stroke device for a random orbital machine has a housing with a central axis and a wall defining a cavity. At least one counterweight is movably disposed at least partially within the cavity. A mounting assembly is disposed at least partially within the cavity. The mounting assembly has a workpiece attachment mechanism. A stroke adjuster couples the at least one counterweight with the mounting assembly. The stroke adjuster enables the at least one counterweight and mounting assembly to move with respect to one another such that a distance between the at least one counterweight and the mounting assembly may be variably adjusted which, in turn, variably adjust a stroke radius of the workpiece attachment mechanism with respect to the central axis of the housing. The stroke adjuster has an adjuster ring and a cam mechanism secured with the adjuster ring.

An electromechanical actuator (EMA) is provided with redundant load paths for driving the actuator stroke. The EMA includes a rotatable screw, a nut mated with the screw and having an external toothed surface, and a rotatable spline member having a splined surface engaging the external toothed surface of the nut. An actuator rod is coupled to the nut for linear movement with the nut. A first motor is operable to rotate the screw relative to the nut to cause the nut to travel linearly along the screw, and a second motor is operable to rotate the spline member and nut such that the nut travels linearly along the screw. Consequently, the actuator rod moves linearly by operation of the first motor alone, by operation of the second motor alone, and by simultaneous operation of the first and second motors. A no-back device may be incorporated into each load path.

An actuator converting a rotary movement into a linear movement is disclosed. The actuator includes a drive means (11), a primary low friction screw mechanism (3, 6, 14) driven by the drive means, a secondary traditional screw mechanism (7, 13) which is connected to the primary screw mechanism and moved linearly by this. The secondary screw mechanism transfers the linear movement to a driven means, such as a clutch. The primary screw mechanism is performing the working stroke proper, while the secondary screw mechanism is arranged to compensate for changes in the engagement point of the driven means. One of the screw mechanisms is provided with a spring (4) making the actuator self-regulating.

The invention relates to an actuator comprising a stationary structure and an actuating element that is movable relative to the stationary structure, a device for locking the actuating element in position which is mounted on the stationary structure and has a state for locking and a state for releasing the actuating element. The locking device comprises, successively, a stress limiter and at least one locking element so arranged as to be butting against one surface of the actuating element, in order to oppose a motion of the actuating element in a predetermined direction. The actuator comprises a member for controlling the locking device in the releasing state thereof and a member for resiliently returning the locking device to the locking state thereof.

A roller screw mechanism comprises a screw having an outer thread and a nut disposed around and coaxially with the screw. The nut comprises an inner thread. A plurality of rollers are disposed radially between the screw and the nut; each roller being provided with an outer thread engaged with the outer and inner threads of the screw and of the nut and with two outer gear teeth. The mechanism also comprises two synchronizing gear teeth that are each engaged with one of the gear teeth of the rollers. An outside diameter of each gear teeth of each roller is less than a diameter of a root of the thread of the roller. Each tooth of the gear teeth of the rollers comprises planar faces that engage with the synchronizing gear teeth.

An apparatus for boring a wellbore, including a bit body having a first end, an inner cavity, and a second end. The first end is connected to a workstring that is configured to deliver a rotational force to the bit body. The inner cavity contains a profile having a first radial cam surface. The second end includes a working face containing a cutting member. The apparatus also includes a pilot bit rotatively connected within the inner cavity. A second radial cam surface is contained on a first end of the pilot bit. The first and second radial cam surfaces are operatively configured to deliver a hammering force. A second end of the pilot bit may include an engaging surface configured to engage a formation surrounding the wellbore. The bit body rotates relative to the pilot bit.

In a ball screw (1), the positioning of the deflectors to the nut is facilitated, and the deflectors are prevented from being dislodged in the radially outward direction from the nut. The ball screw (1) includes a screw shaft (3), a nut (7), a pair of deflectors (13) inserted in respective receiving holes (14) of the nut and a plurality of balls (8). The nut (7) is provided with a guide portion (42) configured to cooperate with a corresponding guide portion (41) provided on the deflector (13) so that the insertion of the deflector (13) into the respective receiving holes (14) is guided in a direction at an angle to the radial direction of the nut.

An improved structure of linear actuator includes an actuator including a gear set having a friction portion located at the periphery of the gear shaft of a driven gear thereof, a one-way bearing mounted on the gear shaft for rubbing against the friction portion to brake the driven gear from reverse rotation, a driver for driving the gear set and a transmission mechanism including a lead screw coaxially coupled to and rotatable by the gear shaft of the driven gear and a retractable tube assembly coupled to the lead screw and movable by the lead screw between an extended position and a received position, and a stopping mechanism including a thrust bearing coupled to the gear shaft of the driven gear and stoppable against an inner race of the one-way bearing inner race to bear an axial thrust load.