A gear unit for a motor vehicle having a rotary bearing supporting a worm gear shaft, rotatable about an axially extending rotation axis, on a housing. The rotary bearing pivotable about a pivot axis and includes a spherical outer face and a stationary pivot ring. The gear unit includes a spring element extending tangentially or circumferentially, at least partially, around the rotation axis, and positioned such that one side engages the housing and the other side, through two axially protruding contact portions lying opposite each other in the direction of the pivot axis, engages the rotary bearing. The spring element includes a ring portion extending transversely to the axial direction and tangentially, at least partially, around the rotation axis.

A vehicle drive unit for a vehicle for omnidirectional driving of the vehicle. The vehicle drive unit includes a vehicle platform, a drive platform, and at least two wheels arranged on the drive platform, one drive unit being provided per wheel to drive the wheel. A controllable self-locking steering actuator is arranged between the drive platform and the vehicle platform. The steering actuator is rotatable about a longitudinal axis and is used to rotate the vehicle platform and the drive platform relative to one another, the steering actuator allowing a temporary blocking of the rotation. At least three pivoting wheels are arranged on the vehicle platform for vehicle stabilisation, each being rotatable about its own wheel axis and about its own vertical axis. A vehicle having a vehicle drive unit is also provide.

A vehicle drive unit for a vehicle for omnidirectional driving of the vehicle. The vehicle drive unit includes a vehicle platform, a drive platform, and at least two wheels arranged on the drive platform, one drive unit being provided per wheel to drive the wheel. A controllable self-locking steering actuator is arranged between the drive platform and the vehicle platform. The steering actuator is rotatable about a longitudinal axis and is used to rotate the vehicle platform and the drive platform relative to one another, the steering actuator allowing a temporary blocking of the rotation. At least three pivoting wheels are arranged on the vehicle platform for vehicle stabilisation, each being rotatable about its own wheel axis and about its own vertical axis. A vehicle having a vehicle drive unit is also provide.

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.

A cylindrical retainer configured to retain balls in a rollable manner is provided inside a ball screw nut. The retainer has retainer grooves each having a shape of an elongated hole that extends in an axial direction of a ball screw shaft so as to be inclined at a predetermined angle. A first end of the ball screw nut and a first end of the retainer, which is one of two ends of the retainer that is closer to the first end of the ball screw nut, are spaced away from each other by a distance. The terminal end of the retainer groove closest to the second end of the retainer and a ball that is closest to the second end of the ball screw nut are spaced away from each other by a distance. The distance is set equal to or larger than the distance.

A ball screw device is provided, including a retainer that can properly retain balls. The difference between a diameter being the pitch circle diameter of the ball screw device and the outside diameter of the rack shaft is set to be equal to or larger than the difference between the bore diameter of a ball screw nut and the diameter. The thickness center diameter of the retainer is set to be smaller than the diameter. Even when the inclination angle is reduced, the clearance between the inclined surfaces of each retainer groove on the radial inside can be easily set to be smaller than the diameter of the balls because the bore diameter of the retainer is set to be smaller. Thus, even when the inclination angle of the inclined surfaces is set to be smaller, the balls can be properly retained.

A ball screw in a steering system has a groove between the inner peripheral surface of a cylindrical ball nut through which a steered shaft extends and the outer peripheral surface of the steered shaft, and balls are accommodated in the groove. The balls rolling and flowing in the groove are returned from downstream to upstream via deflectors and a return passage member disposed in the ball nut. The return passage member has a first connection portion curved to connect one end of a linear portion of the return passage member to the first deflector, and a second connection portion curved to connect the other end of the linear portion to the second deflector. Each connection portion has an opening that opens in the return passage member longitudinal end face and an opening that opens in the return passage member outer periphery of toward the centerline of the ball nut.

A steering system for a vehicle, in particular a utility vehicle, has at least one first steering gear and at least one first steering mechanism for steering at least one first vehicle wheel. The first steering gear is coupled to the first steering mechanism. The steering system has at least one second steering gear and at least one second steering mechanism for steering at least one second vehicle wheel. The second steering gear is coupled to the second steering mechanism. At least one tensioning mechanism is coupled to the first steering gear and to the second steering gear such that the first steering gear and the second steering gear are pre-tensionable with respect to each other, in particular in the idle state and oppositely.

A steering system for a vehicle, in particular a utility vehicle, has at least one first steering gear and at least one first steering mechanism for steering at least one first vehicle wheel. The first steering gear is coupled to the first steering mechanism. The steering system has at least one second steering gear and at least one second steering mechanism for steering at least one second vehicle wheel. The second steering gear is coupled to the second steering mechanism. At least one tensioning mechanism is coupled to the first steering gear and to the second steering gear such that the first steering gear and the second steering gear are pre-tensionable with respect to each other, in particular in the idle state and oppositely.

An apparatus for use in turning steerable vehicle wheels includes a steering member which is axially movable relative to the vehicle to effect turning movement of the steerable vehicle wheels. A ball nut assembly is connected with an externally threaded portion of the steering member. A first motor is connected with the ball nut assembly. The first motor is operable to effect rotation of the ball nut assembly relative to the steering member. A second motor is connected with the ball nut assembly. The second motor is operable to effect rotation of the ball nut assembly relative to the steering member.