Steering system
AssigneeJtekt Corporation
InventorTakashi Tomikawa
Life of this patent
Estimating the term…
Abstract
A rack housing includes first and second rack housing members aligned in the axial direction of the rack shaft and coupled to each other in the vicinity of a speed reducer. A speed reducer casing is provided in its outer wall with a through hole. A belt tension adjusting mechanism includes: an adjusting shaft rotatably attached to the speed reducer casing; an eccentric shaft attached to the outer periphery of the adjusting shaft so as to be rotatable together with the adjusting shaft; two bearings disposed on the outer periphery of the eccentric shaft and axially away from each other; and a tension pulley rotatably attached to the outer periphery of the eccentric shaft via the bearings. A first end of the adjusting shaft is exposed to the outside of the speed reducer casing through the through hole.
Claims7
A steering system comprising:
- a motor;
- a steered shaft including a thread groove, the steered shaft being configured to reciprocate in an axial direction of the steered shaft;
- a ball screw mechanism including a cylindrical nut screwed to the thread groove via a plurality of balls, the ball screw mechanism being configured to provide an axial force to the steered shaft in accordance with rotation of the nut;
- a speed reducer including
- a driven pulley fixed to an outer peripheral surface of the nut disposed inward of the driven pulley,
- a driving pulley fixed to a rotary shaft of the motor so as to be rotatable together with the rotary shaft, and
- a belt wound around the driven pulley and the driving pulley;
- a belt tension adjusting mechanism to adjust a tension of the belt;
- and
- a housing which houses the steered shaft, the ball screw mechanism, the speed reducer, and the belt tension adjusting mechanism, wherein
- the housing includes a first housing member and a second housing member aligned in the axial direction,
- portions of the first and second housing members mating with each other and protruding in a direction perpendicular to the axial direction constitute a speed reducer casing which houses a portion of the speed reducer,
- the speed reducer casing is provided in its outer wall with a through hole passing through the outer wall in the axial direction,
- the belt tension adjusting mechanism includes
- a tension adjustment shaft, and
- a tension pulley rotatably disposed around an outer peripheral surface of the tension adjustment shaft, the tension pulley being configured to abut against the belt,
- the tension adjustment shaft includes
- a first end protruding out of the housing through the through hole,
- a second end housed in the housing, the second end being coaxial with the first end, and
- an eccentric cylindrical portion eccentric relative to a central axis of the first and second ends, the eccentric cylindrical portion being disposed between the first and second ends, and
- the tension adjustment shaft is configured to rotate around the central axis of the first and second ends.
Dependencies are inferred from the claim text.