Abstract: There is provided a ball screw mechanism for which a return of a sphere, such as a conventional circulating ball screw, need not to be considered, and that can prevent vibration and noise and avoid an increase in heat by ensuring smooth movement of a sphere without causing ball jam or the like of a sphere on a screw shaft. The present invention includes a screw shaft 2 that has a spiral groove 2a and extends linearly, a housing 30 that surrounds a periphery of the screw shaft 2, and a plurality of spheres 4 and ball bearings 5 that transmits thrust of the screw shaft 2 to the housing 30. Each ball bearing 5 includes an outer ring 7 attached and fixed to the housing 30 at regular intervals along the spiral groove 2a of the screw shaft 2, and an inner ring 6 provided with a concave spherical contact surface 5a in contact with the sphere 4 on a side surface facing the screw shaft 2. Each inner ring 6 is rotatably disposed about rotation axes N1 to N4 orthogonal to a rotation axis O of the screw shaft 2.

Abstract: In one embodiment, an actuator has a roller, a helical track, and at least one track follower. The roller has a cylindrical body that has a first end, a second end that is offset from the first end along a central axis, and a cylindrical outer surface that extends from the first end to the second end. The helical track is disposed around the cylindrical outer surface in a helical pattern. The at least one track follower can be attached to a load, and rides along the helical track when the roller is rotated about the central axis so as to translate the load along an axial direction that is substantially parallel to the central axis. In some embodiments, the roller has an internal motor that is disposed within the cylindrical body.

Abstract: The disclosure relates to an actuator having a planetary roller screw drive comprising a housing having a cylinder chamber and a fluid reservoir forming one common volume and the housing is filled with a hydraulic fluid. The planetary roller screw drive comprises a spindle having a profiling, which meshes with a plurality of planetary rollers, which are arranged around the spindle and are supported at both ends in a planetary roller carrier. The planetary rollers mesh with an inner profiling of an internal ring gear surrounding the planetary rollers and the planetary rollers are supported in a sleeve surrounding the internal ring gear. According to the disclosure, the planetary roller carrier and/or the sleeve comprise one or more flow ducts connecting the interior and the exterior of a chamber defined radially by the sleeve and axially by the planetary roller carriers to one another.

Abstract: In a roller screw (1) having a screw shaft (2), a plurality of rollers (4) that roll on a flank face (21a) of the screw shaft; and a cage (3) that rotatably houses the plurality of rollers, a plurality of roller groups (40) each having a plurality of rollers arranged at equal intervals while contacting with the same flank face along a spiral groove of the screw shaft for one lead are provided, and the plurality of roller groups are arranged at intervals in the axial direction of the screw shaft. With this configuration, the size of the nut portion in the axial direction of the screw shaft can be prevented from being bloated, and the load distribution in a circumferential direction of the screw shaft can be uniformized.

Abstract: A planetary roller gear drive with a spindle nut (1) that is arranged on a threaded spindle (2) and with planets (3) that are arranged distributed around the periphery and are in rolling engagement with the spindle nut (1) and the threaded spindle (2). The planets (3) revolve on planetary orbits (P) that are arranged perpendicular to the spindle axis and the planets (3) are each divided into multiple planet parts arranged one behind the other in the axial direction.

Abstract: In a roller screw (1) having a screw shaft (2), a plurality of rollers (4) that roll on a flank face (21a) of the screw shaft; and a cage (3) that rotatably houses the plurality of rollers, a plurality of roller groups (40) each having a plurality of rollers arranged at equal intervals while contacting with the same flank face along a spiral groove of the screw shaft for one lead are provided, and the plurality of roller groups are arranged at intervals in the axial direction of the screw shaft. With this configuration, the size of the nut portion in the axial direction of the screw shaft can be prevented from being bloated, and the load distribution in a circumferential direction of the screw shaft can be uniformized.

Abstract: A system and method for propelling a hose, including: a system housing and a tractor element disposed in the housing. The tractor element includes: a tractor housing with a through-bore; and a protrusion extending into the through-bore. The system includes: a hose assembly including a substantially helical coil disposed about a hose; and an actuator for rotating the tractor housing with respect to the system housing. The tractor element is fixed in the system housing with respect to axial movement; and the hose assembly can be disposed in the through-bore so that the protrusion contacts a portion of the coil. As the tractor housing is rotated in a rotational direction: the protrusion exerts a displacement force on the coil; and the hose assembly reacts to the displacement force by displacing in an axial direction.

Abstract: A mechanism for converting rotary motion into linear motion includes a rod having a thread or threaded part at its outer peripheral surface, and a holder member on the outer peripheral surface of the rod, rotatable relative to the rod, and axially movable relative to the rod. Rollers are supported rotatably by the holder member and have annular grooves at their outer peripheral surfaces. Each roller is torsionally disposed at an axial angle greater than or equal to a lead angle of the thread with respect to a central axis of the rod. Both ends of the roller shaft are secured to the holder member, and the mechanism has a structure in which a hole having a diameter greater than that of the roller shaft is provided at one end of the holder member and the roller shaft is secured by a roller mounting member.

Abstract: Push-pull controls utilizing linear and rotational inputs to create linear output are disclosed. One control includes an elongate push rod and a roller pin. The rod has an outer surface, a generally circular cross-section perimeter, a center axis, a proximal end with a user input, and a distal end configured to directly or indirectly interact with an apparatus to be controlled. The rod is rotatable and slidable along the rod axis. The roller pin has a center axis and an outer surface that contacts the push rod outer surface. The roller pin center axis is angularly offset from and non-intersecting with the push rod center axis. The amount of angular offset is greater than zero degrees.

Abstract: Linear actuator device, comprising a housing (2), an externally threaded screw (5) mounted to a piston (9), an internally threaded extended nut (7) and a motor (16) comprising a stator (33) and a rotor element (30) positioned around the extended nut (7), wherein a plurality of first magnets (31) of the rotor element (30) are positioned in relation to the stator (33) such that the stator (33) lies between the extended nut (7) and the first magnets (31) of the rotor element (30). The advantage of the invention is that linear actuators with a high energy density can be manufactured in an easy and cost-effective manner.

Abstract: Provided is a roller screw having an unloaded roller return path of new shape capable of moving rollers smoothly. The roller circulation path of the roller screw has the unloaded roller return path and a loaded roller rolling path. The unloaded roller return path 10 is twisted so that while each roller 4 moves in the unloaded roller return path 10 its central axis is inclined. In a cross sectional shape of the twisted part of the unloaded roller return path 10, each of paired side surface corresponding parts 25c and 25d facing respective side surfaces of the roller 4 is convex toward the inside of the unloaded roller return path 10.

Abstract: A sun shaft, planetary shafts, and a ring shaft having respective axes of rotation in parallel with one another are provided. A helical sun gear, helical planetary gears, and a helical ring gear are provided on the sun shaft, the planetary shafts, and the ring shaft, respectively, and cooperatively constitute a first planetary gear mechanism. A screw sun gear, screw planetary gears, and a screw ring gear 44 are provided on the sun shaft, the planetary shafts, and the ring shaft, respectively, and cooperatively constitute a second planetary gear mechanism. Either of the gear ratio of the screw sun gear to the screw planetary gears and the gear ratio of the screw ring gear to the screw planetary gears differs from the gear ratio of the helical sun gear to the helical planetary gears and from the gear ratio of the helical ring gear to the helical planetary gears.

Abstract: A rotation/linear motion converting mechanism includes a shaft 1 having an external thread 1a on an outer circumferential surface, a nut 2 having an internal thread 2a on an inner circumferential surface, and a roller 3 arranged between the outer circumferential surface of the shaft 1 and the inner circumferential surface of the nut 2. The roller has a thread 3a threaded to the external thread 1a and the internal thread 2a. A spur gear 3b and a spur gear 3c are provided in portions of the roller 3. A spur gear 1b is provided in a portion of the shaft 1. The spur gear 1b is meshed with the spur gear 3b of the roller 3. Internal teeth 4a are provided in a portion of the nut 2. The internal teeth 4a are meshed with the spur gear 3 of the roller 3. This improves the lead accuracy of the shaft 1 when the nut 2 is rotated.

Abstract: Revolving rollers, each provided on an outer peripheral surface thereof with revolving roller grooves extending therearound, are caused to mesh with a rack rod thread of a central rack rod with an axial angle over a lead angle of the rack rod thread and arranged for rotation on a holder member to be twisted. The holder member is rotated round the rack rod by a motor to translate the rack rod. A large thrust can be generated while ensuring a high reliability since a high efficiency is achieved by realizing rolling contact in set points of mesh of the rack rod thread and the revolving roller grooves, points of mesh are made planar, and interference in other points than the points of mesh can be suppressed. Also, play can be restricted by assembling the revolving rollers to the rack rod thread while applying torque in a direction, in which the axial angle is increased.

Abstract: A roller screw of the present invention has a screw shaft 1 having a roller rolling surface 1a spirally formed with a lead on an outer surface thereof; a nut 2 having a roller rolling surface 2a spirally formed on an inner surface thereof to face the roller rolling surface 1a of the screw shaft 1; and a plurality of rollers 4 arranged in a rolling path 3 between the roller rolling surface 1a of the screw shaft 1 and the roller rolling surface 2a of the nut 2 and moving around the screw shaft while rotating on rotation axes of the rollers. In this roller screw, each of the rotation axes 4a of the rollers 4 substantially crosses a center line 1b of the screw shaft 1. Since each of the rotation axes 4a of the rollers 4 crosses the center line 1b of the screw shaft 1 (in other words, the rollers 4 arranged in the rolling path 3 are not skewed from the beginning) even when the rolling path 3 has the lead, the roller 4 are allowed to move smoothly.

Abstract: The present invention provides a screw device which takes a heavy load in one direction along the axis of the screw shaft and only a light load in the opposite direction, the screw device capable of providing ease of control of preloading. The screw device of the present invention has a screw shaft 1 with an outer surface having a ball rolling groove 1a for rolling balls 7 and a roller rolling groove 1b for rolling rollers 6 both spirally formed thereon; a ball nut 4 with an inner surface having a ball rolling groove 4a spirally formed thereon facing the ball rolling groove 1a of the screw shaft 1; a roller nut 5 with an inner surface having a roller rolling groove 5a spirally formed thereon facing the roller rolling groove 1b of the screw shaft 1; a plurality of balls 7 arranged between the screw shaft 1 and the ball nut 4; and a plurality of rollers 6 arranged between the screw shaft 1 and the roller nut 5. The ball nut 4 and the roller nut 5 are connected along an axis of the screw shaft 1.

Abstract: The present invention provides a roller screw capable of circulating rollers smoothly. A roller screw of the present invention has a screw shaft 1 having a roller rolling surface 1a spirally formed with a lead on an outer surface thereof; a nut 2 having a roller rolling surface 2a spirally formed on an inner surface thereof to face the roller rolling surface 1a of the screw shaft 1; and a plurality of rollers 4 arranged in a rolling path 3 between the roller rolling surface 1a of the screw shaft 1 and the roller rolling surface 2a of the nut 2 and moving around the screw shaft while rotating on rotation axes of the rollers. In this roller screw, each of the rotation axes 4a of the rollers 4 substantially crosses a center line 1b of the screw shaft 1.

Abstract: A roller screw structure comprises a nut, a screw and a rolling assembly. The rolling assembly is movably disposed between the nut and the screw and includes at least one rolling cone. The slantwise rolling surface of the rolling cone contacts the spiral groove surfaces of the nut and the screw in a line-to-line manner, and the angle between the rolling surface and the self-rotation axis of the rolling cone is from 0 degree to 6.3 degrees. Thereby, making the distance between the self-rotation axis and the rolling surface of the rolling cone of the rolling assembly different can prevent the occurrence of speed difference caused at different rolling paths of the rolling assembly.

Abstract: A high thrust operator for gate valves employs an inverted satellite roller screw assembly driven by an internally threaded cylinder carried within a bearing case. The cylinder is sized to provide a relief plenum within the case into which the roller screw assembly can be over extended to expose tool engagement flats for attachment and release of a mating stem in the valve gate actuator.

Abstract: A device for converting rotational movement into axial movement includes planetary rollers driven by a drive shaft projecting from a drive device and maintained peripherally at a same distance, in addition to a push body axially displaced by the planetary rollers. These planetary rollers are peripherally fixed on a support which is driven around the axis thereof, the rollers being rotationally mounted and provided with peripheral grooves or threaded grooves; the support is connected in a fixed manner to the drive shaft rotating around its axis; the planetary rollers engage in at least one thread-like groove of the push body that is displaced along the axis of the support by means of their peripheral grooves or threaded grooves.

Abstract: In a rectilinear motion driving apparatus, a shaft is fitted into a cylindrical body in a coaxial state, and a plurality of cylindrical coil rollers are interposed between the cylindrical body and the shaft by press fit so as to roll at a predetermined inclined angle to the axial direction. These cylindrical coil rollers are contacted with an outer peripheral surface of the shaft and an inner peripheral surface of the cylindrical body with a pressure contact force, and the cylindrical body or the shaft is rotated so that the shaft or the cylindrical body makes a rectilinear motion toward an axial direction. A pressure contact force of both inner and outer surfaces of the cylindrical coil roller to the cylindrical body and the shaft is set either higher or lower in the vicinity of the end portion thereof than the intermediate portion of the cylindrical body.

Abstract: The present invention discloses a dual directional power feed for use with handheld drills or stationary frame mounted power sources. The device comprises a housing, two pairs of wheel bearings rotatably mounted to the housing, a cap rotatably mounted to the housing, and a biasing bearing rotatably mounted to the cap. The cap is rotatable to a first position such that rotation of the threaded cable in a first direction causes the threaded cable to translate along its longitudinal axis in a first direction. The cap is further rotatable to a second position such that rotation of the threaded cable in the first direction causes the threaded cable to translate along its longitudinal axis in a second direction, opposite the first direction. Further, the present invention discloses a bearing and support assembly for coupling a power feed device to a power unit comprising a support plate and a bearing.