A rack bush of a steering device for a vehicle may include: a bush body part installed in a rack housing of the steering device for a vehicle so as to cover a rack bar, and configured to guide the rack bar to move in an axial direction; a first uneven part formed in an uneven shape on an outer circumferential surface of the bush body part, and configured to bring the bush body part and the rack housing into line contact with each other; and a position fixing part formed at one end of the bush body part, and configured to prevent the bush body part from moving in the axial direction.

In a ball screw device, an inner peripheral rolling groove of a nut includes, between openings of mounting holes, a constant pitch circle diameter region where a pitch circle diameter is constant and gradually-changing pitch circle diameter regions where the pitch circle diameter gradually increases, in the ranges from opposite ends of the constant pitch circle diameter region to the respective openings. At least the constant pitch circle diameter region has a surface hardness greater than or equal to a predetermined value, among the constant pitch circle diameter region and the gradually-changing pitch circle diameter regions excluding edges at the boundaries between the respective openings and the inner peripheral rolling groove, and the edges at the boundaries between the respective openings and the inner peripheral rolling groove have a surface hardness less than the predetermined value.

A method for vehicle stabilization includes, in response to a determination that a fault occurred in a rear steering mechanism, identifying a fault type associated with the fault. The method also includes determining whether a position of a rack of the rear steering mechanism is controllable based on the fault type. The method also includes, in response to a determination that the position of the rack is controllable, selectively positioning the rack to a center position and holding, using a motor control system of the rear steering mechanism, the rack in the center position. The method also includes, in response to a determination that the position of the rack is not controllable, holding, using the motor control system of the rear steering mechanism, the rack in a current position.

Methods and apparatus to determine rack force are disclosed. An example apparatus includes a rack to couple to a steering knuckle of a vehicle, a ball nut engaged with the rack, a first ring gear coupled to the ball nut, a first pinion fixed to a motor, the first pinion engaged with the first ring gear, the motor to rotate the ball nut to move the rack, a motor encoder to detect a rotation of the first pinion, a second ring gear coupled to the ball nut, and a sensor fixed to a second pinion, the second pinion engaged with the second ring gear, the second pinion to rotate as the second ring gear rotates, the sensor to detect a rotation of the second pinion, the rotation of the second pinion and the rotation of the first pinion corresponding to a force on the rack.

To reduce the effect of a steering operation on feeling. A rack bush comprises: a bush body that is accommodated in a cylindrical housing, supports a load exerted on a rack bar while allowing the rack bar to move in the direction of an axial center O, and can be extended and retracted in a radial direction; and an elastic ring mounted on the bush body. The bush body has a mounting groove for mounting the elastic ring, the mounting groove being formed peripherally in an outer peripheral surface, and the mounting groove having a large-diameter part where the circumferential radius of a groove bottom is a first radius r1, and a small-diameter part where said radius is a second radius r2 that is less than the first radius r1. This configuration allows the formation of an elastic ring protruding part, in which the elastic ring protrudes greatly from the outer peripheral surface of the bush body, and an elastic ring embedded part, in which the elastic ring is embedded in the outer peripheral surface of the bush body.

A rack bar includes: a rack tooth row including a plurality of rack teeth meshing with pinion teeth; a hardened layer provided continuously over an entire circumference of the rack tooth row; and a center portion provided inside the hardened layer and having lower hardness than the hardened layer. When the rack bar is viewed in an axial direction of the rack bar, a depth of the hardened layer from the following positions i), ii), and iii) increases in this order: i) a bottom land of the rack teeth; ii) a side of the rack bar relative to the bottom land; and iii) a back of the rack bar relative to the bottom land.

An ATV is shown having a steering system comprised of a power steering unit having drive and driven pitman arms coupled to a drag link. The drive pitman arm is laterally offset from a vehicle centerline and is driven by the power steering unit. An alternate power steering system includes a pack and pinion subassembly coupled to a power steering motor, which then couples to steering arms of the ATV.

A method is proposed for operating a steering system of a motor vehicle, in particular an electromechanically supported steering system. First, at least one first virtual magnet and one second virtual magnet are provided in the steering system of the motor vehicle. A virtual magnetic force exerted on each other by the multiple virtual magnets is determined. A setpoint force that is to be applied to a lower part of the steering system is estimated and an auxiliary force with which a servo motor of the steering system acts on the lower part of the steering system is determined from the specified virtual magnetic force and the estimated setpoint force.

A steering device includes: a rack shaft; a rack housing housing the rack shaft; a motor unit having a motor case of which one end is coupled to the rack housing; a moving force application mechanism that moves the rack shaft by an output of the motor unit; and a support member that is fixed to the rack housing and supports the motor case. The rack housing has a fixing projection in which a bolt hole extending in a height direction is formed. The support member has an arc-shaped support part that extends along an outer circumferential surface of the motor case, and a pair of fixing pieces that protrudes from the support part toward a rack shaft housing section. Ends of the pair of fixing pieces are fastened with a bolt to the fixing projection of the rack housing.

A rack bar blank material includes a rack portion configured to mesh with a pinion in an end side of a hollow shaft material in an axial direction, and an end portion which is provided closer to the end side of the hollow shaft material than the rack portion. The end portion has a diameter which is larger than that of a minimum circle embracing a section of the rack portion which is perpendicular to the axial direction and which is equal to that of a shaft portion at the other end side of the shaft material in the axial direction.