Electric power steering system for vehicles
First Claim
1. An electric power steering system for vehicles comprising:
- an input shaft operatively connected to a steering wheel;
an output shaft operatively connected to a steered wheel;
an electric motor for operatively supplying auxiliary torque to said output shaft;
means for detecting steering torque acting on said input shaft;
means for detecting a steering speed of said input shaft; and
driving control means for feeding said electric motor with a drive signal based on output signals from said steering torque detecting means and said steering speed detecting means, said driving control means controlling said electric motor to produce said auxiliary torque and said driving control means controlling said electric motor to rotate at a speed in correspondence to said steering speed so that said rotational speed of said motor corresponds to said steering speed, said driving control means outputting a motor control signal and feeding said motor control signal to said electric motor, said driving control means including a motor driving means for receiving said motor control signal and for feeding said drive signal to said electric motor in accordance with said motor control signal, whereinsaid driving control means determines an armature current necessary for the electric motor, depending on the output signal of the steering torque detecting means, and determines an armature voltage to be applied to the electric motor depending on a steering speed represented by the output signal from the steering speed detecting means and the armature current; and
the drive signal to be fed from the driving control means to the electric motor includes an armature voltage signal.
1 Assignment
0 Petitions
Accused Products
Abstract
An electric power steering system for vehicles including a driving control circuit (76, 100, 108) for feeding, in consideration of an output signal (S1, S2) from a steering torque dectection mechanism (77) for detecting steering torque (Ts) acting on an input shaft (4), a drive signal (Va) to an electric motor (33) for producing auxiliary torque to be supplied to an output shaft (7). The steering system further comprises a detection mechanism (82) for detecting the steering speed (Ns) of the input shaft (4), and the driving control circuit (76, 100, 108) is adapted to feed the drive signal (Va) to the electric motor (33) in consideration of an output signal (S4, S5) from the steering speed detection mechanism (82) as well as of the output signal (S1, S2) from the steering torque detection mechanism (77). The driving control circuit (76, 100, 108) includes a micro-computer unit (76) for determining by address designation a control signal (T3, T4 , T5) as basis of the drive signal (Va) to the elecric motor (33), depending on the output signal (S1, S2) from the steering torque detection mechanism (77) and the output signal (S4, S5) from the steering speed detection mechanism (82).
58 Citations
8 Claims
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1. An electric power steering system for vehicles comprising:
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an input shaft operatively connected to a steering wheel; an output shaft operatively connected to a steered wheel; an electric motor for operatively supplying auxiliary torque to said output shaft; means for detecting steering torque acting on said input shaft; means for detecting a steering speed of said input shaft; and driving control means for feeding said electric motor with a drive signal based on output signals from said steering torque detecting means and said steering speed detecting means, said driving control means controlling said electric motor to produce said auxiliary torque and said driving control means controlling said electric motor to rotate at a speed in correspondence to said steering speed so that said rotational speed of said motor corresponds to said steering speed, said driving control means outputting a motor control signal and feeding said motor control signal to said electric motor, said driving control means including a motor driving means for receiving said motor control signal and for feeding said drive signal to said electric motor in accordance with said motor control signal, wherein said driving control means determines an armature current necessary for the electric motor, depending on the output signal of the steering torque detecting means, and determines an armature voltage to be applied to the electric motor depending on a steering speed represented by the output signal from the steering speed detecting means and the armature current; and the drive signal to be fed from the driving control means to the electric motor includes an armature voltage signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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Specification