US 12,252,192 B2
Steering device
Shogo Ishikawa, Higashimatsuyama (JP); and Takashi Sasaki, Higashimatsuyama (JP)
Assigned to KNORR-BREMSE COMMERCIAL VEHICLE SYSTEMS JAPAN LTD., Sakado (JP)
Appl. No. 18/569,358
Filed by KNORR-BREMSE COMMERCIAL VEHICLE SYSTEMS JAPAN LTD., Sakado (JP)
PCT Filed Jun. 8, 2022, PCT No. PCT/JP2022/023067
§ 371(c)(1), (2) Date Dec. 12, 2023,
PCT Pub. No. WO2022/264890, PCT Pub. Date Dec. 22, 2022.
Claims priority of application No. 2021-098408 (JP), filed on Jun. 14, 2021.
Prior Publication US 2024/0270306 A1, Aug. 15, 2024
Int. Cl. B62D 5/24 (2006.01); B62D 3/08 (2006.01)
CPC B62D 5/24 (2013.01) [B62D 3/08 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A steering device comprising:
rack teeth formed at an outer side of a ball nut screwed onto a steering shaft that is linked to a steering wheel;
a sector gear provided at a sector shaft that is linked to steered wheels, wherein the sector gear has a plurality of sector teeth including a central tooth that is most deeply engaged with the rack teeth when the sector shaft is at a neutral position which corresponds to a straight-ahead steering state, the plurality of sector teeth including the central tooth are provided in a circumferential direction of the sector shaft, and the sector gear is engaged with the rack teeth by the plurality of sector teeth including the central tooth; and
a preload applying mechanism adjusting engagement between the rack teeth and the sector gear in a vicinity of the neutral position of the sector shaft, wherein
the preload applying mechanism is provided at one end portion in a tooth width direction of a specific tooth bottom of the rack teeth, which faces a tooth tip of the central tooth when the sector shaft is in the vicinity of the neutral position,
the preload applying mechanism forces the ball nut to one side in a rotation direction of the ball nut by a reaction force generated by elastic contact of the preload applying mechanism with the tooth tip of the central tooth
the preload applying mechanism includes:
a plunger receiving hole formed at the specific tooth bottom,
a plunger which is accommodated in the plunger receiving hole so as to be able to move forward and backward and whose top end side can protrude from an opening, facing the sector gear, of the plunger receiving hole, and
a forcing member interposed between a bottom of the plunger receiving hole and the plunger and forcing the plunger toward the central tooth,
one end side in an axial direction of the sector shaft with respect to the sector gear, which is a side connected to a pitman arm, is formed so as to have a relatively large diameter, and the other end side in the axial direction of the sector shaft with respect to the sector gear is formed so as to have a relatively small diameter as compared with that of the one end side in the axial direction of the sector shaft, and
the plunger receiving hole is provided at one of both end portions in the tooth width direction of the specific tooth bottom, which corresponds to the other end side in the axial direction of the sector shaft.