US 12,145,663 B2
Rack-driven electric power assisted steering device
Jong Baek Lee, Yongin-si (KR)
Assigned to HL MANDO CORPORATION, Pyeongtaek-si (KR)
Appl. No. 17/436,422
Filed by HL MANDO CORPORATION, Pyeongtaek-si (KR)
PCT Filed Feb. 25, 2020, PCT No. PCT/KR2020/002670
§ 371(c)(1), (2) Date Sep. 3, 2021,
PCT Pub. No. WO2020/184866, PCT Pub. Date Sep. 17, 2020.
Claims priority of application No. 10-2019-0026684 (KR), filed on Mar. 8, 2019.
Prior Publication US 2022/0126909 A1, Apr. 28, 2022
Int. Cl. B62D 5/04 (2006.01); B62D 5/00 (2006.01)
CPC B62D 5/0448 (2013.01) [B62D 5/003 (2013.01); B62D 5/0424 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A rack-driven power-assisted steering device, comprising:
a rack bar axially sliding inside a rack housing and having an outer circumferential screw groove formed in an outer circumferential surface thereof;
a ball nut having an inner circumferential screw groove formed in an inner circumferential surface thereof, the inner circumferential screw groove corresponding to the outer circumferential screw groove of the rack bar, a ball circulation path axially formed through the ball nut between the inner circumferential surface and the outer circumferential surface;
an end cap having a ball return hole to circulate a ball along the ball circulation path, the outer circumferential screw groove, and the inner circumferential screw groove, the end cap coupled to each of a first end and a second end of the ball circulation path; and
a supporting member coupled to the inner circumferential surface of the ball nut while axially supporting the end cap,
wherein the ball nut has a small-diameter portion and a large-diameter portion at the inner circumferential surface thereof, the small-diameter portion having the inner circumferential screw groove, and the large-diameter portion having a larger diameter and provided on two opposite ends of the small-diameter portion, and wherein the supporting member is coupled to an inner circumferential surface of the large-diameter portion,
wherein the supporting member has a seating groove in an axial outer surface thereof, and wherein an elastic member is fitted into the seating groove to elastically support the supporting member radially.