US 2017/0252637 A1 · Lean-to-Steer Mechanisms with Linear or Non-linear Steering Responses

Abstract

The present steerable wheel assembly incorporates a lean-to-steer mechanism into an inner race of a roller bearing, while a wheel is mounted to an outer race of the roller bearing. A shaft extending from the mechanism is attached to a body, and the mechanism acts to steer the outer race and the wheel about a vertical steering axis when the shaft is tilted about a horizontal axis. The mechanism can be a pivot joint, providing a linear steering response, or can be a lean-to-steer mechanism that provides a non-linear response where the steering action is not consistently responsive to tilting over the expected range of tilting. The present non-linear lean-to-steer mechanisms can also be incorporated into alternative lean-to-steer devices, and alternative mechanisms can employ tracking structures to coordinate tilting motion of a first moving element with steering motion of a second moving element to provide a non-linear lean-to-steer response.

Claims20

Dependent claims

A lean-to-steer mechanism for mounting at least one wheel to a body that traverses a nominally horizontal surface and for steering the at least one wheel about a nominally vertical steering axis in response to leaning of the body about a nominally horizontal longitudinal axis, the lean-to-steer mechanism having:

an inner spherical element;
a shaft attached to said inner spherical element and extending therefrom;
an outer spherical socket in which said inner spherical element is rotatably mounted so as to be rotatable about a central point,
one of said shaft and said outer spherical socket being mounted to the body and the other of said shaft and said outer spherical socket having the at least one wheel rotatably mounted thereto so as to rotate about a horizontal wheel axis;
and
means for limiting the motion of said inner spherical member in said outer spherical socket such that tilting of the one of said shaft and said spherical socket that is mounted to the body, which results from leaning of the body about the longitudinal axis, causes the other of said shaft and said spherical socket to rotate about the steering axis to maintain the wheel axis horizontal,
said means for limiting the motion being configured such that the rotation about the steering axis responsive to tilting is a non-linear response.

4 more elements

A steerable wheel assembly for a body that traverses a nominally horizontal surface and for steering about a nominally vertical steering axis in response to leaning of the body about a nominally horizontal longitudinal axis, the steerable wheel assembly having:

a shaft maintained in a fixed position relative to the body so as to extend perpendicular to the longitudinal axis;
a roller bearing defining a roller bearing axis and having an inner race and an outer race that rotate freely with respect to each other about the roller bearing axis;
a wheel mounted to said outer race and having a rim that rests upon the horizontal surface, said wheel being configured to maintain the roller bearing axis substantially parallel to the horizontal surface at least at a desired speed of operation;
and
means for limiting the motion between said shaft and said inner race such that tilting of said shaft resulting from leaning of the body about the longitudinal axis causes said inner race to rotate about the steering axis to maintain the roller bearing axis horizontal.

2 more elements

a first moving element affixed with respect to the body;
a second moving element having the at least one wheel rotatably mounted thereto so as to rotate about a horizontal wheel axis,
said second moving element being rotatably mounted to said first moving element so as to be rotatable with respect thereto about a central point that resides at the intersection of the steering axis and the longitudinal axis;
and
means for limiting the motion of said first moving element with respect to said second moving element such that tilting of said first moving element, which results from leaning of the body about the longitudinal axis, causes said second moving element to rotate about the steering axis to maintain the wheel axis horizontal,
said means for limiting the motion being configured such that the rotation about the steering axis responsive to tilting is a non-linear response.

3 more elements

Dependencies are inferred from the claim text.

Lean-to-Steer Mechanisms with Linear or Non-linear Steering Responses

Life of this patent

Lean-to-Steer Mechanisms with Linear or Non-linear Steering Responses

Life of this patent

Abstract

Claims20