The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 09, 2002
Filed:
Jan. 18, 2001
Edward H. Phillips, Troy, MI (US);
Techco Corporation, Southfield, MI (US);
Abstract
Vehicle power steering systems ( and ) achieve substantially linear control relationships between and applied steering torque input Ts and a resulting steering force output, that is, a powered assist to vehicle steering. Impedance matching means utilized for coupling an electric motor ( ) to the steering load respectively include speed reduction means ( ), torque summing means ( ) and force generating means ( ) in the systems ( and ). The speed reduction means ( ) comprises gear reduction means ( ) and a supplemental pinion. The torque summing means ( ) comprises steering column ( ) coupled gear reduction means ( ), and, the force generating means ( ) comprises hydraulic transmission means including a power cylinder ( ). The systems ( and ) are preferably regenerative. The systems ( and ) each utilize internal closed-loop servo control of the electric motor ( ) to substantially eliminate stability control problems including, for example, a low frequency stability control problem which has typically not been overcome in prior EPS systems.