A nonpropellant inertial device to propel structures on and off earth is disclosed. Secured on a rigid planar base are electrically powered motors for two crankshafts. Pair of parallel linkages are connected between the crankshafts and the sides of a freely rotatable cylintrical weight. The crankshafts rotate differentially to create straight-line reciprocating motion to the linkages. The linkages are design to only pull the cylindrical weight from one side then the other causing the weight to rotate back and forth in reciprocal motion, traverse to the straight-line motion of the linkages. High frequency impulses alternate from the sides of the cylintrical weight with each impulse being a simultaneous action-reaction event. However, only part of the angular action to the weight, directly opposes the straight-line reaction to the crankshafts. Therefore, a net amount of reaction remains to impart unidirectional inertial propulsion to the mover. Two similar cylintrical weight systems are generally used for cancelling out lateral vibrations to the mover.

An electric linear actuator has an electric motor, a speed reduction mechanism, and a ball screw mechanism to convert rotational motion of the electric motor to an axial linear motion of a drive shaft. The ball screw mechanism nut and screw shaft both include helical screw grooves with a large number of balls between them. The housing has a first housing portion and a second housing portion. The electric motor is mounted on the first housing portion. The second housing portion abuts an end face of the first housing portion. The first housing portion has a cylindrical gear containing portion to contain the speed reduction mechanism. An end part of the gear containing portion extends radially inward to form a bottom portion to cover the speed reduction mechanism. The bottom portion of the first housing portion and the second housing portion are formed, respectively, with abutment surfaces.

A device includes a transmission assembly having a first override clutch. The first override clutch is used especially for transmitting a torque between a first coupling partner and a second coupling partner. The first override clutch engages and disengages in accordance with a change in the load flow between the coupling partners. A freewheeling member which is associated with the first override clutch neutralizes the engagement between the coupling partners. The neutralization is, in particular, temporary.

A device includes a transmission assembly having a first override clutch. The first override clutch is used especially for transmitting a torque between a first coupling partner and a second coupling partner. The first override clutch engages and disengages in accordance with a change in the load flow between the coupling partners. A freewheeling member which is associated with the first override clutch neutralizes the engagement between the coupling partners. The neutralization is, in particular, temporary.

A wiper and scraper assembly for a linear motion assembly has a wiper and a scraper constructed from separate pieces of material. The wiper has a width extending between opposite sides with an opening extending through the opposite sides, with a first helical thread of the wiper being received in an external groove of a screw of the linear motion assembly. The scraper is disposed in the opening of the wiper, and has a second helical thread received in the external groove of the screw. The wiper has at least one lubrication return plow extending into one of its opposite sides, with the lubrication return plow facing axially inwardly into a nut of the linear motion assembly. The wiper has at least one debris ejection plow formed in the first helical thread, with the debris ejection plow facing axially outwardly from the ball nut.

Various embodiments include a fastening unit for fastening a tendon to a system. The fastening unit comprises: a head with a first opening; a shaft with a second opening and an external thread; and a channel extending from the first opening along the head to the second opening at least partly along the shaft. The external thread and the channel in each case accommodate the tendon.

A rod rotator has a crankshaft with non-aligned crank journals, a first actuating pawl attached to the first crank journal and a second actuating pawl attached to the second crank journal, and a ratchet wheel connected to a polished rod. The first actuating pawl pushes on the ratchet wheel to rotate the ratchet wheel while the second actuating pawl pulls on the ratchet wheel to rotate the ratchet wheel at the same time.

A rod rotator has a crankshaft with non-aligned crank journals, a first actuating pawl attached to the first crank journal and a second actuating pawl attached to the second crank journal, and a ratchet wheel connected to a polished rod. The first actuating pawl pushes on the ratchet wheel to rotate the ratchet wheel while the second actuating pawl pulls on the ratchet wheel to rotate the ratchet wheel at the same time.

An actuator for level adjustment of a motor vehicle utilizes a ball screw and a locking unit provided for blocking the ball screw. The actuator has a spindle drive which can be actuated by an electric motor via a gear. The spindle may be fastened to a damper of the chassis of a motor vehicle, to a wheel carrier or to the body or a subframe of a motor vehicle. With the aid of a locking unit of the spindle drive, the rotation of the spindle nut can be optionally blocked or enabled. The locking unit includes a locking element which engages a locking contour attached to the end face of a rotatable element of the gear.

A roller guide wheel contains a single set of spherical bearings and is constructed with a precision outer race machined into the guide wheel interior and an inner race formed by the surfaces of two conically-tapered set screws that affix the roller guide wheel within a housing made part of a stage slider. The roller guide wheel, which contacts a rail on one side of the stage body and exhibits a non-nutating axis of rotation, serves as way for the translating slider. The way on the opposing side of the slider is a set of v-groove contacts that make sliding contact with a rail on the corresponding side of the stage body. A flexure is machined into the slider permitting preload of the slider contacts points with the rails. The stage geometry permits a large slider through-hole and the use of alternative way mechanisms with the roller guide wheel.