Abstract: A rotary glide system for a downhole tool includes a shaft having a plurality of helical grooves formed into an outer surface of the shaft, and a ball bearing sleeve configured to fit around the shaft. The ball bearing sleeve includes a plurality of helical grooves formed into an inner surface of the sleeve, a first slot that extends from a first end of the ball bearing sleeve and intersects a helical groove of the plurality of helical grooves, and a first ball stop comprising a first tab that extends into the first slot of the ball bearing sleeve.

Abstract: A ball screw assembly includes a screw shaft along which is formed a first helical groove; a nut along which is form a second helical groove; the first helical groove and the second helical groove cooperating to define a track, a plurality of balls arranged in the track and configured to move along the track in response to relative motion between the screw shaft and the nut such that rotational motion of the screw is translated to linear motion of the nut via the balls and vice versa. The assembly also includes a bypass shoe arranged between the nut and the track and spaced from the track by a predetermined preload X, wherein when a load applied to the nut exceeds the predetermined preload, the bypass shoe engages with the track such that motion of the screw is transferred to motion of the nut via the shoe and bypasses the balls.

Abstract: A device is described wherein an actuator (3, 4; 103, 104) drives a member, such as a rack (6) meshed with a pinion (5), between two stable positions. For this purpose, elements for stopping the movable member are provided, which cooperate with elements present on the outer housing (2, 21), in which the actuator and the movable member (5, 51) are arranged, for holding at least one of said stable conditions. The device of the invention ensures low energy consumption because the actuator (3) only operates for moving the movable member from one stable position to the other.

Abstract: A delivery catheter for a stent. The delivery catheter may comprise a distal end and a proximal end. The distal end includes a stent attachment region adapted to receive a stent. The stent may be of the self-expanding type. The catheter further comprises a handle at its proximal end and at least one sheath which may at least partially circumferentially cover said stent such as to retain it in a collapsed configuration. The sheath is coupled at its proximal end to an actuator located on said handle portion.

Abstract: A ballscrew assembly may include a ballnut configured to combat the negative effects of thermal expansion of dissimilar materials used within the ballscrew assembly. Moreover, the ballscrew assembly described herein may have a decreased coefficient of friction as compared with a steel on steel housing and ballnut configuration. A ballscrew assembly may comprise a ballnut made from a first material, a ballnut housing made from a second material, and a sleeve made from a third material. The sleeve may be positioned between the exterior of the ballnut and an interior of the ballnut housing to reduce friction between the exterior surface of the ballnut and an interior surface of the ballnut housing.

Abstract: A rotational-to-linear conversion mechanism inhibits interference from occurring in places except for an engagement site to increase the efficiency of conversion mechanism and reliability, which has: a rack rod 1 including thread on its outer peripheral face; a holder member 3 provided on the outer periphery of the rack rod, rotating about the rack rod and moving in the axis direction; and revolving rollers 21 rotatably supported in the holder member, each having ring-shaped grooves formed in its outer peripheral face to be engaged with the thread, and placed at an axis angle with respect to a center axis of the rack rod to allow the ring-shaped grooves to be engaged with the thread on the rack rod. A contact face of the thread with each ring-shaped groove in an engagement site of the thread and the ring-shaped groove is formed as a convex face having different curvatures in a radial direction.

Abstract: A lead screw apparatus includes a screw shaft having a spiral channel on an outer circumferential surface thereof, a plurality of rollers rotatable with contact with the spiral channel, and a cage rotatably supporting the rollers for conversion between relative rotation and linear motions between the screw shaft and the cage bi-directionally. The lead screw apparatus further includes a bearing and a holder 6 supported by the case for supporting the bearing. An inner ring of the bearing and the roller are integrally formed. An outer ring of the bearing has a protrusion on an outer circumferential surface thereof on a side closer to the screw shaft. Rollers of the bearing having a circular truncated cone shape are disposed in the bearing in a circumferential direction with substantially no gap. The outer ring has a thread part to shift the bearing and the roller.

Abstract: The invention relates to a ball screw (36) for a motor vehicle brake (10), in particular for an electromechanically actuable motor vehicle brake, comprising a rotatable spindle (38), a nut (40) that is axially movable relative to the spindle (38) in accordance with the rotation thereof and a rolling body arrangement (42) that is disposed between, and displaceable relative to, the spindle (38) and the nut (40). In this ball screw it is provided that the rolling body arrangement (42) is preloaded into a predetermined normal position by means of at least one spring element (46). The invention further relates to a vehicle brake having such a ball screw.

Abstract: A rolling element screw device is provided with a power transmission mechanism for moving a retainer ring 14 in an axial direction in accordance with lead angles of spiral grooves 11a, 12a while rotating the retainer ring 14 in a condition of maintaining a constant relationship with respect to a rotational phase of a rotating side member in accordance with the rotation of the rotating side member. The power transmission mechanism is provided with an external tooth 17 formed to a screw member 11, an internal tooth 18 formed to a nut member 12 and a plurality of planetary gears 19 held to be rotatable to circumferentially predetermined positions of the retainer ring 14 in a condition meshed with the external tooth 17 and the internal tooth 18, respectively, the external tooth 17 is formed so as not to overlap with the screw side spiral groove 11a formed to the screw member 11, and the internal tooth 18 is formed so as not to overlap with the nut side spiral groove 12a formed to the nut member 12.