A linear actuator comprising a spindle-based linear drive (1) having an inner threaded spindle (5) and an outer element (2) surrounding the threaded spindle (5), in which the threaded spindle (5) can be moved in the axial direction; and a telescopic housing (20) with a first telescope part (21) and a second telescope part (22), which is surrounded at least in part by the first telescope part (21). On its side facing the first telescope part (21), the second telescope part (22) has an adapter part (24) that is connected rotationally fixedly to the second telescope part (22) and has a central opening. The linear drive has a connecting element (30) that is mounted on the outer element (2) and comprises snap elements (31) that are engaged with the central opening of the adapter part (24) in such a manner that the connecting element (30) is held in the adapter part (24).

The present invention relates to a linear drive (1), comprising a drive shaft (10) that can be rotated about a longitudinal axis (X), at least one propulsion element (20) having a propulsion tooth (21), a rack (30), and at least one guide means (40), wherein the at least one propulsion element (20) is coupled to the drive shaft (10) in such a way that the propulsion tooth (21) of said element is pressed into the rack (30) in a cyclical movement (21) during a rotation of the drive shaft (10) about the longitudinal axis (X) to generate an advance, and wherein, when the propulsion tooth (21) of the at least one propulsion element (20) is pressed into the rack (30), the at least one guide means (40) forms an abutment which counteracts the rack (30) for the at least one propulsion element (20). In addition, the present invention relates to a longitudinal adjustment unit and a motor vehicle.

In order to improve linear drives on aircraft with regards to backlash, gear reduction, self-lock capability, load transfer and wear, a linear drive device is provided that has a first member with engaging teeth, such as a tooth rack and a second member which functions as a drive unit. The second member includes a plurality of movable teeth that are actuated by a cam shaft. The cam shaft has a control cam portion that is shaped such that the movable teeth perform a wave-like motion that forces the first member along its longitudinal direction relative to the second member.

A harmonic drive assembly and fluid-powered linear motors with both axial pistons are rotary piston arrangements incorporating the harmonic drive assembly are disclosed. The motors may be used in downhole drilling applications, but the drive assembly and/or motors may be used in other applications. The assembly, motors and methods use advanced harmonic drives, advanced helical drives, and combinations thereof with 1) motors with axial pistons and reciprocating linear rings to convert reciprocative axial motion to continuous rotary motion, and 2) motors with rotary pistons and reciprocating linear rings to rectify reciprocative rotary motion to continual rotary motion to improve performance over prior configurations. Axial pistons provide a robust simple solution for generating rotation; Rotational pistons provide increased torque generation as the torque generated is proportional to motor length. Since downhole drills are long, a high-torque motor can be produced using this method.

The present invention provides a rotary shaft assembly applied to a novel clutch system that ensures a 100% torque transmission rate between an engine and a transmission in a vehicle system and can be commonly applied to conventional manual transmission vehicles and automatic vehicles. The rotary shaft assembly converts linear motion of one member to rotary motion of another member, using a combination of a protrusion and an inclined guide slot.

In order to improve linear drives on aircraft with regards to backlash, gear reduction, self-lock capability, load transfer and wear, a linear drive device is provided that has a first member with engaging teeth, such as a tooth rack and a second member which functions as a drive unit. The second member includes a plurality of movable teeth that are actuated by a cam shaft. The cam shaft has a control cam portion that is shaped such that the movable teeth perform a wave-like motion that forces the first member along its longitudinal direction relative to the second member.

Torque of a prime mover is input into a sun gear. A planetary gear revolves in a circumferential direction of the sun gear while rotating and meshing with the sun gear. A carrier has an annular shape, rotatably supports the planetary gear, and is rotatable relative to the sun gear. A first ring gear is fixed to a housing, and meshes with the planetary gear. A second ring gear meshes with the planetary gear, is different from the first ring gear in number of teeth of a tooth portion, and outputs torque to a rotation portion. At least a part of the sun gear in an axial direction is located radially inward of the carrier. At least a part of the first ring gear and at least a part of the second ring gear in the axial direction are located radially outward of the carrier.

Torque of a prime mover is input into a sun gear. A planetary gear revolves in a circumferential direction of the sun gear while rotating and meshing with the sun gear. A carrier has an annular shape, rotatably supports the planetary gear, and is rotatable relative to the sun gear. A first ring gear is fixed to a housing, and meshes with the planetary gear. A second ring gear meshes with the planetary gear, is different from the first ring gear in number of teeth of a tooth portion, and outputs torque to a rotation portion. At least a part of the sun gear in an axial direction is located radially inward of the carrier. At least a part of the first ring gear and at least a part of the second ring gear in the axial direction are located radially outward of the carrier.

A sun gear of a speed reducer is provided coaxially with and integrally rotatably with a rotor of a prime mover. Multiple planetary gears are disposed in a circumferential direction of the sun gear, and are capable of revolving in the circumferential direction of the sun gear while rotating in a state of meshing with the sun gear. A carrier rotatably supports the planetary gears, and is rotatable relative to the sun gear. A first ring gear is fixed to a housing, and has a first ring gear tooth portion capable of meshing with the planetary gears. A second ring gear is rotatable integrally with a rotation portion, and has a second ring gear tooth portion capable of meshing with the planetary gears. The second ring gear tooth portion is different in number of teeth from the first ring gear tooth portion.

A housing includes an accommodation space for a prime mover and a speed reducer. A rotational translation unit includes a rotation portion that rotates relative to the housing upon receiving torque outputted from the speed reducer, and a translation portion that moves relative to the housing in an axial direction according to rotation of the rotation portion. The accommodation space is between the rotation portion and the housing. A clutch in a clutch space allows or interrupts transmission of torque between a first transmission portion and a second transmission portion. The rotation portion is between the clutch space and the accommodation space. A sealing member has an annular shape in contact with the rotation portion, and maintains an air-tight or liquid-tight state between the accommodation space and the clutch space.