A helical gear transmission for an electromechanical servo steering mechanism may include a shaft that meshes with a helical gear. The shaft may be arranged in a transmission housing and, at its first end, may be mounted in a drive-side bearing arrangement so as to be rotatable about an axis of rotation. At its second end, the shaft may be mounted in a drive-remote bearing arrangement in the transmission housing. The drive-side bearing arrangement may have a rolling bearing, an outer ring of which is spherical. The rolling bearing may be enclosed by two bearing shells. The outer side of the outer ring may have two flat points that are opposite one another and form a pivot axis about which the shaft is pivotable in a direction of the helical gear.

Belt driven rotary assist apparatus for recirculating ball steering gears are disclosed. An example motor vehicle steering system includes an input shaft to couple to a steering shaft of a motor vehicle, a worm gear, a first end of the worm gear coupled to the input shaft, a second end of the worm gear fixed to a helical spur gear, a ball nut surrounding a portion of the worm gear, the ball nut including ball bearings and ball guides, a first pulley wheel fixed to a pinion, the first pulley wheel engaged with a belt, the pinion engaged with the helical spur gear, a motor fixed to a second pulley wheel, the second pulley wheel engaged with the belt, the motor to rotate the worm gear to translate the ball nut, and a sector gear engaged with the ball nut, the sector gear to rotate as the ball nut translates.

A noise reduction structure of an electronic power steering apparatus including a worm shaft rotated by a motor, a worm wheel engaged in the worm shaft and rotating a steering shaft, and a housing surrounding the worm shaft includes a cylindrical damper unit formed as an elastic member in an inner side of the cylindrical damper unit for absorbing a shock transmitted to the worm shaft and rotatably connected to the worm shaft, a rubber holder coupled to a semi-cylindrical damper holder formed on a side surface of the damper unit for making a close contact between the worm shaft and the worm wheel, and a plug unit including a plug holder formed on a lower end of a side surface of the plug unit for coupling to the rubber holder and fixed to the housing on the other side of the plug unit.

An electric power steering system with a worm gear includes a worm shaft and a worm wheel, wherein an electric motor is associated with the worm shaft, which is connected to the worm shaft in a force-transmitting manner. A bearing element, arranged on the worm shaft at the end of the worm shaft facing away from the electric motor, is received in a guide bush, wherein the guide bush has, on its circumferential side, a passage opening. It is provided a pre-tensioning device comprising a spring-loaded actuator element extending through the passage opening of the guide bush and acting on the worm shaft in the direction of the worm wheel with a defined pre-tensioning force (K), wherein the pre-tensioning device comprises a limiting device which is adapted to limit a pivoting movement that displaces the worm wheel away from the worm shaft. Furthermore, it is proposed a method for the production of steering systems and a test system for performing the method.

According to electric power steering apparatuses of these embodiments, power of a motor is secondarily reduced and a torque is amplified by connecting a worm wheel and a steering shaft using a cycloid gear, a weight and a cost of the motor can be reduced, and various reduction ratios can be realized, and a secondary deduction structure can be realized while minimizing a change in the structure of an existing reducer.

An electric power steering apparatus and a control method thereof. A motor includes a first motor providing power to move a rack and a second motor providing power to move the rack in synchronization with the first motor. A sensor includes a torque angle sensor detecting a torque value and a steering angle in response to manipulation of a steering wheel and an angle sensor detecting an angle of rotation of a sector shaft. A controller controls the motor in response to the manipulation of the steering wheel, calculates an amount of compensation rotation of the motor by comparing the steering angle and the angle of rotation, and controls an amount of rotation of the motor in accordance with an amount of compensation rotation. The amount of rotation of a vehicle's wheel is controlled, so that actual intention of the driver in steering is accurately reflected.

A method for assembling a rack-and-pinion steering gear may involve introducing a steering pinion into a housing opening of a steering gear housing such that a region of a narrowed portion of a pinion shaft is situated at a level of a rack to be inserted, introducing the rack into the housing opening of the steering gear housing such that the rack is pushed past the narrowed portion of the pinion shaft into a setpoint position, and moving the pinion shaft farther into the steering gear housing to an end position such that a toothing region of the rack enters into engagement with a toothing of the steering pinion.

Disclosed herein is a damping coupler of an electronic steering apparatus. The damping coupler includes a first spline having a first shaft hole such that a worm shaft is inserted therein, with a first serration being formed in the first shaft hole to engage with a serration of the worm shaft; a second spline coupled to a side of the first spline, and having a second shaft hole such that the worm shaft is inserted therein, with a second serration being formed in the second shaft hole to engage with a serration of the worm shaft; and a molding surrounding outsides of the first and second splines, and coupled to a motor shaft.

A coupling assembly includes a flexible coupling and a first adapter. The flexible coupling defines an opening that extends along a central longitudinal axis between a first coupling end and a second coupling end. The first adapter is arranged to be at least partially received within the opening proximate the first coupling end. The first adapter extends between a first adapter first face and a first adapter second face. The first adapter defines a first adapter post and a first adapter hole. The first adapter post that extends from the first adapter first face. The first adapter hole that extends from the first adapter first face towards the first adapter second face.

A magnetostrictive torque sensor is provided that is capable of maintaining high detection accuracy, even when an excessive torque acts on a rotary shaft. The magnetostrictive torque sensor includes a magnetostrictive film 71 that is arranged on a second steering shaft 23, or a rotary shaft, having a substantially columnar shape so as to surround the second steering shaft 23 around its axis, and detects a rotational torque about the axis acting on the second steering shaft 23 based on a change in a magnetic property of the magnetostrictive film 71. Compressive stress remains on an outer circumferential surface of a sensor region 77 of the second steering shaft 23 around which the magnetostrictive film 71 is arranged. A plated layer of the magnetostrictive film 71 is arranged on the outer circumferential surface of the sensor region 77 in which compressive stress remains.