CROSS REFERENCE TO RELATED APPLICATION

This application claims priority from Korean Patent Application No. 10-2018-0114145, filed on Sep. 21, 2018, which is hereby incorporated by reference for all purposes as if fully set forth herein.

BACKGROUND

Field

Embodiments relate to a vehicle steering apparatus and, more particularly, to a vehicle steering apparatus having a structure by which the durability of a sensor rotor to heat and abrasion can be improved, the flatness of the sensor rotor can be prevented from being lowered during calking for coupling of the sensor rotor to a steering shaft so that steering torque of a driver can be more accurately detected, a fabrication process can be simplified, and fabrication costs can be reduced.

Description of Related Art

A steering shaft includes an input shaft connected to a steering wheel, an output shaft connected to a pinion shaft engaged with a rack bar, and a torsion bar connecting the input shaft and the output shaft. A torque sensor and a rotor are coupled to each of the input shaft and the output shaft to detect torque, generated in response to a driver manipulating the steering wheel, and to transmit a signal indicating the torque to an electric control unit (ECU). In this manner, the manipulation feel for the driver, the reliability of the vehicle, and the like can be improved.

That is, when a driver rotates the input shaft by manipulating the steering wheel, the torsion bar is tilted at a predetermined angle, so that the input shaft and the output shaft have a phase difference therebetween, then steering torque is calculated depending on the strength of the torsion bar.

The phase difference between the input shaft and the output shaft is obtained by the torque sensor detecting a phase difference with respect to a rotor. The rotor includes blades facing the torque sensor and a sleeve coupled to the blades and the output shaft.

However, in a steering apparatus of the related art, the sleeve formed of plastic and the blades formed of steel are connected by molding, which, may result in a complicated fabrication process. In particular, the sleeve formed of plastic may be deformed or abraded in a high-temperature environment, and the flatness of the rotor may be lowered. Accordingly, an accurate phase difference may not be obtained, which is problematic.

Alternatively, in the steering apparatus of the related art, the sleeve and the blades are separately formed of steel and are then coupled by welding. However, even in this case, a fabrication process may be complicated. In particular, the flatness of the sleeve may be lowered during calking, so that an accurate phase difference may not be obtained, which is problematic.

BRIEF SUMMARY

Various aspects provide a vehicle steering apparatus having a structure by which the durability of a sensor rotor to heat and abrasion can be improved, the flatness of the sensor rotor can be prevented from being lowered during calking for coupling of the sensor rotor to a steering shaft so that steering torque of a driver can be more accurately detected, a fabrication process can be simplified, and fabrication costs can be reduced.

The object of the present disclosure is not limited to the aforementioned description, and other objects not explicitly disclosed herein will be clearly understood by those having ordinary knowledge in the technical field, to which the present disclosure pertains, from the description provided hereinafter.

According to an aspect, a vehicle steering apparatus may include: a first shaft to which one which one end of a torsion bar and a torque sensor are coupled; a second shaft to which the other end of the torsion bar is coupled, the second shaft having a recess in an outer circumferential surface of one end portion thereof; and a sensor rotor comprising an annular body coupled to the outer circumferential surface of the one end portion of the second shaft, with a stepped portion being provided in an inner circumferential surface thereof to be open in one axial direction, and blades protruding from outer circumferential portions of the body to face the torque sensor.

According to exemplary embodiments, the durability of the sensor rotor to heat and abrasion can be improved, the flatness of the sensor rotor can be prevented from being lowered during calking for coupling of the sensor rotor to the steering shaft so that steering torque of a driver can be more accurately detected, a fabrication process can be simplified, and fabrication costs can be reduced.

