Steering device

Abstract

A steering device includes a first housing, first and second cables, and first and second sheaths. The first housing includes a first part that supports a rotatable first cable pulley, and a second part that is disposed for relative displacement with respect to the first part. The first cable is at least partially wound on the first cable pulley in a first direction of rotation. The second cable is at least partially wound on the first cable pulley in a second direction of rotation. The first sheath surrounds the first cable and extends between first and second ends, and the first end of the first sheath is coupled to the second part of the first housing. The second sheath surrounds the second cable and extends between first and second ends, and the first end of the second sheath is coupled to the second part of the first housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate preferred embodiments of the invention, and together with the general description given above and the detailed description given below, serve to explain features of the invention.

FIG. 1 is a diagram showing a steer-by-wire (SBW) system including a first embodiment of a cable-based steering device.

FIG. 2 is a perspective view of a steering side cable pulley part in accordance with the first embodiment.

FIG. 3 is an exploded view of the steering side cable pulley part in accordance with the first embodiment.

FIG. 4 is a cross sectional view of a first pulley case in accordance with the first embodiment.

FIG. 5 is an enlarged cross sectional view of a first cable tension adjustment mechanism in accordance with the first embodiment.

FIG. 6 is a cross sectional view of a related cable-based steering device showing a pulley casing part with a cable tension adjustment mechanism.

FIGS. 7(A) to 7(D) explain the cable tension adjustment function of the related cable-based steering device shown in FIG. 6.

FIGS. 8( a) to 8(e) explain the cable tension adjustment function of the steering side cable pulley part in accordance with the first embodiment.

FIG. 9 is an enlarged cross sectional view of a cable tension adjustment mechanism in accordance with a second embodiment.

FIG. 10 is an enlarged cross sectional view of a cable tension adjustment mechanism in accordance with a third embodiment.

FIG. 11 is a vertical cross sectional view of the cable tension adjustment mechanism in accordance with the third embodiment.

FIG. 12 is an enlarged cross sectional view of a cable tension adjustment mechanism in accordance with a fourth embodiment.

FIG. 13 is a vertical cross sectional view of the cable tension adjustment mechanism in accordance with the fourth embodiment.

Claims

1. A steering device, comprising: a first housing including: a first part supporting a first cable pulley for relative rotation with respect to the first housing; anda second part being disposed for relative displacement with respect to the first part of the first housing;a second housing supporting a second cable pulley for relative rotation with respect to the second housing;a first cable at least partially wound on the first cable pulley in a first direction of rotation of the first cable pulley;a second cable at least partially wound on the first cable pulley in a second direction of rotation of the first cable pulley;wherein the first cable and the second cable are wound on the second cable pulley so that the first pulley and second pulley are rotationally coupled via the first and second cables;a first sheath extending between first and second ends, the first cable being slidingly disposed in the first sheath, and the first end of the first sheath being coupled to the second part of the first housing; anda second sheath extending between first and second ends, the second cable being slidingly disposed in the second sheath, and the first end of the second sheath being coupled to the second part of the first housing;wherein one of the first and second cable pulleys is adapted to rotate in response to an actuation part being operated by a driver, and the other of the first and second cable pulleys is adapted to rotate a wheel turning part to turn a steering control wheel.

2. The steering device according to claim 1, further comprising: an adjuster being disposed between the first and second parts of the first housing;wherein a first actuation of the adjuster simultaneously increases tension in the first and second cables, and a second actuation of the adjuster simultaneously decreases tension in the first and second cables.

3. The steering device according to claim 2, wherein the adjuster comprises: a shaft including first and second portions, at least a first one of the first and second portions threadingly engaging a first one of the first and second parts of the first housing, and a second one of the first and second portions engaging a second one of the first and second parts of the first housing;wherein rotation of the shaft causes relative displacement of the first and second parts of the first housing.

4. The steering device according to claim 3, wherein the adjuster comprises: a turning operator rotating the shaft; anda locking member preventing rotation of the shaft with respect to the second part of the first housing.

5. The steering device according to claim 4, wherein the turning operator comprises a wheel fixed to the shaft between the first and second portions, the first portion of the shaft comprises right-handed threads threadingly engaging the first one of the first and second parts of the first housing, the second portion of the shaft comprises left-handed threads threadingly engaging the second one of the first and second parts of the first housing, and the locking member comprises a nut threadingly engaging one of the first and second portions of the shaft and adapted to abuttingly engage one of the first and second parts of the first housing.

6. The steering device according to claim 4, wherein the turning member comprises a wheel fixed to the shaft between the first and second portions, the first portion of the shaft comprises threads threadingly engaging the first one of the first and second parts of the first housing, the second portion of the shaft comprises a thrust bearing coupling the shaft to the second one of the first and second parts of the first housing, and the locking member comprises a nut threadingly engaging the first portion of the shaft and adapted to abuttingly engage the first one of the first and second parts of the first housing.

7. The steering device according to claim 1, further comprising: at least one adjuster being disposed between the first and second parts of the first housing;wherein a first actuation of the at least one adjuster simultaneously increases tension in the first and second cables, and a second actuation of the at least one adjuster simultaneously decreases tension in the first and second cables.

8. The steering device according to claim 7, wherein each of the at least one adjuster comprises: a shaft including first and second portions, at least a first one of the first and second portions threadingly engaging a first one of the first and second parts of the first housing, and a second one of the first and second portions threadingly engaging a second one of the first and second parts of the first housing;wherein rotation of the shaft causes relative displacement of the first and second parts of the first housing.

9. The steering device according to claim 7, further comprising: a turning operator rotating the shaft of the at least one adjuster; anda locking member preventing rotation of the turning operator with respect to the second part of the first housing.

10. The steering device according to claim 9, wherein the turning operator comprises: a worm wheel disposed at approximately a center of each shaft of the at least one adjuster;a worm gear shaft supported for relative rotation with respect to the second part of the first housing;at least one worm gear fixed to the worm gear shaft, each at least one worm gear cooperatively engaging a corresponding worm wheel of the at least one adjuster; anda detent bolt threadingly engaging the second part of the first housing, the detent bolt being adapted to contact the worm gear shaft so as to prevent relative rotation of the worm gear shaft with respect to the second part of the first housing.

11. The steering device according to claim 10, wherein the at least one adjuster comprises first and second adjusters, the first adjuster being disposed proximate to the first end of the first sheath, and the second adjuster being disposed proximate to the first end of the second sheath.

12. The steering device according to claim 10, wherein the first ends of the first and second sheaths define an imaginary plane, and the worm gear shaft extends perpendicular to the imaginary plane.

13. The steering device according to claim 1, wherein the first and second parts of the first housing define telescopically related tubular parts that are relatively displaceable along an axis parallel to take-up and pay-out directions of the first and second cables with respect to the first cable pulley.

14. The steering device according to claim 13, wherein the tubular parts comprise: a pair of first guiding convex surfaces extending from the first part of the first housing and slidingly engaging the second part of the first housing; anda pair of second guiding convex surfaces extending from the second part of the first housing and slidingly engaging the first part of the first housing, the pair of second guiding convex surfaces being axially displaced with respect to the pair of first guiding convex surfaces.

15. The steering device according to claim 13, further comprising: a first adjuster being disposed between the first and second parts of the first housing; anda second adjuster being disposed between the first and second parts of the second housing;wherein actuation of the first adjuster simultaneously adjusts tension in the first and second cables, and actuation of the second adjuster simultaneously adjusts tension in the first and second cables.

16. The steering device according to claim 1, further comprising: a second housing including: a first part supporting a second cable pulley for relative rotation with respect to the second housing; anda second part disposed for relative displacement with respect to the first part of the second housing;wherein the first cable is at least partially wound on the second cable pulley in a first direction of rotation of the second cable pulley, the second cable is at least partially wound on the second cable pulley in a second direction of rotation of the second cable pulley, and the second ends of the first and second sheaths are coupled to the second part of the second housing.

17. A steering device, comprising: a first cable at least partially wound on a first cable pulley in a first direction of rotation of the first cable pulley;a second cable at least partially wound on the first cable pulley in a second direction of rotation of the first cable pulley;a first sheath extending between first and second ends, the first cable being slidingly disposed in the first sheath, and the first end of the first sheath being disposed proximate to the first cable pulley;a second sheath extending between first and second ends, the second cable being slidingly disposed in the second sheath, and the first end of the second sheath being disposed proximate to the first cable pulley; andmeans for adjusting simultaneously a relative displacement between the first cable pulley and each of the first ends of the first and second sheaths.