Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
224 words
A control system for an electrically powered vehicle of the type having dual drive motors with series connected armature windings and separately excited field windings, said dual motors being arranged such that one motor thereof is provided for each of two driven wheels on a common axle line for which one wheel assumes a radially inside position and the other a radially outside position with respect to a turning radius of the vehicle, comprising: means providing a tractive effort signal representative of a desired tractive effort to be exerted by said driven wheels; armature regulating means providing current to said series connected armatures in proportion to said tractive effort signal; field regulating means providing a first excitation signal according to which excitation of each field winding is regulated; means providing a turning radius signal representative of a selected turning radius for said vehicle; means responsive to said turning radius signal to provide an inside wheel signal and an outside wheel signal, said signals being related to each other such that an increase or decrease in one signal value results in a corresponding decrease or increase in the other, the sum of said values being a constant; and means adjusting one corresponding field winding excitation in accordance with the outside wheel signal and the other field winding excitation in accordance with the inside wheel signal.
Claim 2
Dependent Claim
224 words
A control system for an electrically powered vehicle of the type having dual drive motors with series connected armature windings and separately excited field windings, said dual motors being arranged such that one motor thereof is provided for each of two driven wheels on a common axle line for which one wheel assumes a radially inside position and the other a radially outside position with respect to a turning radius of the vehicle, comprising: means providing a tractive effort signal representative of a desired tractive effort to be exerted by said driven wheels; armature regulating means providing current to said series connected armatures in proportion to said tractive effort signal; field regulating means providing a first excitation signal according to which excitation of each field winding is regulated; means providing a turning radius signal representative of a selected turning radius for said vehicle; means responsive to said turning radius signal to provide an inside wheel signal and an outside wheel signal, said signals being related to each other such that an increase or decrease in one signal value results in a corresponding decrease or increase in the other, the sum of said values being a constant; and means adjusting one corresponding field winding excitation in accordance with the outside wheel signal and the other field winding excitation in accordance with the inside wheel signal.
Claim 3
Dependent Claim
35 words
The control system of claim 1 further including: means providing a feedback signal proportional to said armature current; and wherein said field regulating means provides said first excitation signal in accordance with said feedback signal.
Claim 4
Dependent Claim
26 words
The control system of claim 2 wherein said inside wheel signal decreases in value and said outside wheel signal increases in value for shorter turning radaii.
Claim 5
Dependent Claim
74 words
The control system of claim 3 wherein said outside wheel signal is provided proportional to ##EQU10## and said inside wheel signal is provided proportional to ##EQU11## R being a ratio of inside wheel speed to outside wheel speed proportional to ##EQU12## Where: L=distance between said common axle line and the center line of a steering wheel; W=distance between said driven wheels; θ ST =a steering cycle of the vehicle related to said turning radius.
Claim 6
Dependent Claim
90 words
The control system of claim 4 wherein said turning radius signal and said inside and outside wheel signals are in analog form and said means responsive to said turning radius signal comprises a lookup table including: an analog to digital converter for converting said turning radius signal to digital form; a memory unit addressable by said digital signal and storing values of said inside and outside wheel signals in digital form; a pair of digital to analog converters for converting said digital inside and outside wheel values to analog form.
Claim 7
Dependent Claim
62 words
The control system of claim 5 wherein said means for adjusting field winding excitation comprises left and right multipliers, one of which provides one excitation adjustment as the product of said inside wheel signal and said first excitation signal and the other of which provides the other excitation adjustment as the product of said outside wheel signal and said first excitation signal.