A ball screw having a threaded stem including a ball groove formed in an outer surface thereof, a ball nut including a central bore formed by an inner surface thereof, the inner surface defining a ball groove, a first recess extending inwardly from an end face of the ball nut and into the ball groove of the inner surface, and a stop pin disposed in the first recess so that a first end of the stop pin extends inwardly into the ball groove of the inner surface of the ball nut, wherein the stop pin is formed by a coiled strip of metal.

A ball screw device includes a screw shaft that has a first helical groove on an outer circumference, a nut that has a second helical groove on an inner circumference, a plurality of balls, a stopper provided at an end portion of the second helical groove, and a spring body that is placed between an end portion ball closest to the stopper and the stopper. The spring body is configured of a plurality of coil springs arrayed along the first helical groove and the second helical groove. The coil springs that are adjacent each have a spring end portion of which rigidity is higher than rigidity of a spring middle portion.

A ball screw assembly having a ball nut including a first end, a second end, a central bore, and a ball track defined by the inner surface, a ball screw shaft including an outer surface defining a ball track, the ball screw shaft being disposed in the central bore so that the ball tracks form a ball raceway, a first stopper disposed within the ball raceway, a plurality of main balls forming a ball train, the ball train being disposed in the ball raceway, and a main spring assembly disposed in the ball raceway between a first end of the ball train and the first stopper, wherein a spring constant of the first spring portion is greater than a spring constant of the second spring portion.

A ball-screw actuator includes a screw nut having a metal core and an over-molded plastic outer shell. The plastic outer shell includes features which would be expensive to manufacture in a single piece metal screw nut, such as an anti-rotation feature, an axial position control feature, and a lateral position control feature. The anti-rotation feature may take the form of an axial groove or of an axial ridge.

A ball screw includes a ball screw spindle, and a ball screw nut extending about the ball screw spindle. The ball screw nut has internal threading that corresponds with external threading of the ball screw spindle to define a raceway for rolling elements. The ball screw nut includes one or more bore holes extending from the exterior surface of the ball screw nut, and partially into the ball screw nut. The bore hole defines an end stop. A spring has one end that contacts the end stop, and another end that contacts one of the rolling elements.

A ball screw drive includes two screw drive parts (3, 4), namely a lead screw (3) and a nut (4). The ball screw drive also includes a deflection element (6) for the individual deflection of balls (5) is inserted into a recess (7), formed by one of the screw drive parts (3, 4), such that a gap (16) is formed between the base (15) of the recess (7) and the deflection element (6), and such that lateral contact surfaces (17) of the deflection element (6) which are located next to the recess (7) rest on the screw drive part (3, 4).

Ball screw rotary actuator with ball cage. In one embodiment, a ball screw rotary actuator includes an outer cylinder, a piston, and inner shaft. Outer ball bearings travel in helical groove between the outer cylinder and position to rotate the piston as it translates due to fluid pressure. The inner shaft is situated radially inward of the piston, and straight grooves are disposed between the piston and the inner shaft. Inner ball bearings travel in the straight grooves and rotate the inner shaft as the piston rotates. The ball screw rotary actuator also includes an outer ball cage to position the outer ball bearings in a spaced configuration, an outer indexing gear to control a position of the outer ball cage, an inner ball cage to position the inner ball bearings in a spaced configuration, and an inner indexing gear to control a position of the inner ball cage.

Ball screw rotary actuator with independent ball paths. In one embodiment, a ball screw rotary actuator includes an outer cylinder including a fluid port, a piston configured to translate within the outer cylinder due to fluid pressure, helical grooves disposed between the outer cylinder and the piston, and outer ball bearings configured to travel in the helical grooves to rotate the piston within the outer cylinder as the piston translates. The ball screw rotary actuator also includes an inner shaft situated radially inward of the piston, straight grooves disposed between the piston and the inner shaft, and inner ball bearings configured to travel in the straight grooves, and to rotate the inner shaft as the piston rotates.

A production method of a ball screw device is provided. The ball screw device includes a ball screw portion, a ball nut, rolling balls, and a retainer. The production method of the ball screw device includes: a first preparation step of preparing a nut subassembly as a standard product; a second preparation step of preparing the ball screw portion in plurality by types as ranked products; a measuring step of measuring a relative displacement in a thrust direction between the standard product and each ranked product; a determination step of determining whether the displacement meets a displacement specification; a replacing step of, if the displacement does not meet the specification, replacing the ranked product with another ranked product; and an assembling step of, if the displacement meets the specification, assembling the standard product and the ranked product into the ball screw device.

A ball screw device including a low-cost retainer that is disposed between a ball screw shaft and a ball nut and has a flange portion, a steering system using the ball screw device, and a method for producing the retainer of the ball screw device are provided. The ball screw device includes the ball screw shaft, the ball nut, rolling balls, and the retainer. Both side surfaces of each of retainer grooves are formed so as to allow radially outward movement of the rolling balls and to restrict radially inward movement thereof, and the retainer has a weld joint at both of the opposite ends of each retainer groove in the axial direction of the retainer.