Steering system for automotive vehicles
AssigneeNissan Motor Co., Ltd.
InventorHiroshi Mouri
Life of this patent
Estimating the term…
Abstract
A steering system for an automotive vehicle provides an improved steering response characteristic and has has an elastic member which is included in a transmission path from a steering wheel to tires of the vehicle to be operated by the steering wheel, such as a steering column coupling which is elastically deformed according to the rotation of a steering column shaft, or a rack insulator for elastically supporting a rack housing of a rack/pinion steering mechanism. The elastic member is comprised of a spring element and a damping element of which the ratio C/K of the damping coefficient C to the spring constant K is such that C/K is greater than 1/(10.pi.).
Claims21
A steering system for an automotive vehicle, comprising:
- a steering wheel to be manually operated by a driver;
- and
- a steering device for transmitting a steering input from the steering wheel to a tire of the vehicle, said steering device including an elastic member having a spring element with a spring constant and a damping element with a damping coefficient,
- wherein an actual steering angle of said tire defines a steering output of said steering device,
- wherein the elastic member has a spring constant K and a damping coefficient C such that C/K>1/(10.pi.) and
- wherein the elastic member comprises blended rubber.
A steering system for an automotive vehicle, comprising:
- a steering wheel to be manually operated by a driver;
- and
- a steering device for transmitting a steering input from the steering wheel to tires of the vehicle, each of said tires being carried by a knuckle arm with a length l and having a spring constant K.sub.2, said steering device including
- a rack/pinion steering gear mechanism having a gear ratio N accommodated in a housing which is elastically supported on a body of the vehicle by an elastic insulator comprised of a spring element having a spring constant K.sub.1 and a damping element having a damping coefficient C.sub.1,
- a steering column shaft connected to the steering wheel, and
- an elastic column coupling arranged between the steering column shaft and a pinion of the rack/pinion steering gear mechanism, said elastic column coupling comprised of a spring element having a spring constant K.sub.0 and a damping element having a damping coefficient C.sub.0,
- wherein an actual steering angle of said tires defines a steering output of said steering device,
- wherein one of the elastic insulator and the elastic column coupling has a spring constant K and a damping coefficient C such that C/K>1/(10.pi.), and
- wherein said one of the elastic insulator and the elastic column coupling comprises blended rubber.
A method for tuning steering characteristics of an automotive vehicle, said method comprising the steps of:
- determining a spring constant K of an elastic member to be arranged in a steering device of said automotive vehicle;
- determining a damping coefficient C of the elastic member;
- and
- if the spring constant K and the damping coefficient C have a ratio C/K which is less than 1/(10.pi.), then selecting a blended rubber whose damping coefficient C' and spring constant K' are such that C'/K'>1/(10.pi.) as the elastic member.
Dependencies are inferred from the claim text.