The present invention relates to a linear drive (1), comprising a camshaft (10) having at least one camshaft disk (15) which is arranged in a longitudinal axis (X), at least one rack (30) comprising at least one tooth (31), and at least one propulsion element (20) having at least one propulsion tooth (21), wherein the at least one propulsion element (20) has a recess (25) with which the camshaft (10) engages, wherein the camshaft (10) is coupled to the at least one propulsion element (20) by means of the at least one camshaft disk (15), and wherein the propulsion element (20) can be pushed into and out of the rack (30) in order to generate a propulsion in the longitudinal axis (X) when the camshaft (10) rotates. In addition, the present invention relates to a longitudinal adjustment unit for a seat and to a motor vehicle having at least one longitudinal adjustment unit.

A movable rack assembly may include an input shaft, a driven gear, an adjustable rack, an interference plate, and a contact tab. The input shaft may extend along an input axis. The input shaft may include a worm gear segment disposed along the input axis between a first end and a second end. The driven gear may be enmeshed with the worm gear segment, define a maximum outer circumference, and be rotatable about a driven axis nonparallel to the input axis. The interference plate may be fixed to the driven gear. The interference plate may include a radial arm extending past the maximum outer circumference of the driven gear. The contact tab may extend from the input shaft and be axially offset from the worm gear segment in selective engagement with the radial arm at a predefined travel limit of the driven gear to halt rotation at the input shaft.

A movable rack assembly may include an input shaft, a driven gear, an adjustable rack, an interference plate, and a contact tab. The input shaft may extend along an input axis. The input shaft may include a worm gear segment disposed along the input axis between a first end and a second end. The driven gear may be enmeshed with the worm gear segment, define a maximum outer circumference, and be rotatable about a driven axis nonparallel to the input axis. The interference plate may be fixed to the driven gear. The interference plate may include a radial arm extending past the maximum outer circumference of the driven gear. The contact tab may extend from the input shaft and be axially offset from the worm gear segment in selective engagement with the radial arm at a predefined travel limit of the driven gear to halt rotation at the input shaft.

The double pendulum in dynamic motion generates chaotic movement. The current invention integrates two double pendulums with electronic controllers to control the chaotic movement, and a transmission set to use the controlled motion to spin a shaft. The electronic controller provides impulse to each double pendulum and controls the frequency of the oscillations to generate a constant swinging bi-directional motion of the double pendulums. The upper ends of the double pendulums are coupled to a reciprocating transmission set that transforms the swinging bi-directional motion of each double pendulum into a unidirectional spinning motion, transmitted to a horizontal shaft, generating a constant speed as output.

The present disclosure relates to a power assist control apparatus and a power assist control method. The power assist control apparatus according to the present disclosure comprises: a main motor driven at a first rotation speed; a sub-motor driven at a second rotation speed; and a controller which receives steering information from a steering wheel to calculate a target rotation speed value of an output shaft, and controls the main motor and the sub-motor such that the output shaft is rotated at the target rotation speed.

Pawls in a lifter device, having: outer teeth that are rotatably supported by shafts for in lock plates and are meshed with inner teeth of a base; and pins that are provided in an intermediate section in the radial direction, between the shaft center of the shafts and the teeth tips of the inner teeth, and are pressed in the rotation direction by a rotation transmittance plate during a release operation. The pins have a protruding shape that protrudes from the pawls in the thrust direction.

Pawls in a lifter device, having: outer teeth that are rotatably supported by shafts for in lock plates and are meshed with inner teeth of a base; and pins that are provided in an intermediate section in the radial direction, between the shaft center of the shafts and the teeth tips of the inner teeth, and are pressed in the rotation direction by a rotation transmittance plate during a release operation. The pins have a protruding shape that protrudes from the pawls in the thrust direction.

A driving force transmission device includes a drive gear, a driven gear, which includes a gear portion and a partially toothless gear portion, rotates by the gear portion meshing with the drive gear, stops rotating in response to the partially toothless gear portion facing the drive gear, a first cam member and a second cam member which operate in conjunction with the driven gear, a first elastic member for urging the first cam member, a follower member to which urging force is applied by a second elastic member and which is moved by the second cam member, and a contact portion for coming into contact with the first cam member by urging force of the first elastic member. The first cam member includes a home cam surface for coming into contact with the contact portion so that rotation of the driven gear is limited.

A driving force transmission device includes a drive gear, a driven gear, which includes a gear portion and a partially toothless gear portion, rotates by the gear portion meshing with the drive gear, stops rotating in response to the partially toothless gear portion facing the drive gear, a first cam member and a second cam member which operate in conjunction with the driven gear, a first elastic member for urging the first cam member, a follower member to which urging force is applied by a second elastic member and which is moved by the second cam member, and a contact portion for coming into contact with the first cam member by urging force of the first elastic member. The first cam member includes a home cam surface for coming into contact with the contact portion so that rotation of the driven gear is limited.

With respect to a linear motion shaft in which a rack shaft part and a ball screw shaft part are joined to each other by friction welding, coaxiality of a portion having a rack shaft part and a portion having a ball screw shaft part is improved. In a state where a gripped portion 56 formed on the screw shaft part 29 is gripped by a first gripping tool 57 for centering, and a rack shaft part 28 is gripped by a second gripping tool 58 for centering, end portions in the axial direction of the rack shaft part 28 and the screw shaft part 29 are abutted to each other while the screw shaft part 29 and the rack shaft part 28 are relatively rotated by rotating the first gripping tool 57, so that the rack shaft part 28 and the screw shaft part 29 are joined to each other by friction welding.