Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
200 words
An electric power steering system (200) for vehicles, comprising: an input shaft (4) operatively connected to a steering wheel (6); an output shaft (5) operatively connected to a steered wheel; an electric motor (18) for operatively supplying auxiliary torque to said output shaft (5); torque detecting means (31) for detecting steering torque (Ts) acting on said input shaft (4); and drive control means (30, 45, 53) for giving said electric motor (18) a drive signal (Va), taking into consideration an output signal (S 1 , S 2 ) from said torque detecting means (31), wherein: said steering system (200) further comprises: means (35) for detecting the steering speed (Ns) of said input shaft (4); and means (115, 116, 122-126, 130-132) for detecting the steering acceleration (dNs) of said input shaft (4); and said drive control means (30, 45, 53) is adapted to give said motor drive signal (Va) to said electric motor (18), taking into consideration an output signal (S 3 , S 4 ) from said steering speed detecting means (35) and an output signal (dNs) from said steering acceleration detecting means (115, 116, 122-126, 130-132) in addition to said steering torque signal (S 1 , S 2 ).
Claim 2
Dependent Claim
200 words
An electric power steering system (200) for vehicles, comprising: an input shaft (4) operatively connected to a steering wheel (6); an output shaft (5) operatively connected to a steered wheel; an electric motor (18) for operatively supplying auxiliary torque to said output shaft (5); torque detecting means (31) for detecting steering torque (Ts) acting on said input shaft (4); and drive control means (30, 45, 53) for giving said electric motor (18) a drive signal (Va), taking into consideration an output signal (S 1 , S 2 ) from said torque detecting means (31), wherein: said steering system (200) further comprises: means (35) for detecting the steering speed (Ns) of said input shaft (4); and means (115, 116, 122-126, 130-132) for detecting the steering acceleration (dNs) of said input shaft (4); and said drive control means (30, 45, 53) is adapted to give said motor drive signal (Va) to said electric motor (18), taking into consideration an output signal (S 3 , S 4 ) from said steering speed detecting means (35) and an output signal (dNs) from said steering acceleration detecting means (115, 116, 122-126, 130-132) in addition to said steering torque signal (S 1 , S 2 ).
Claim 3
Dependent Claim
199 words
An electric power steering system for vehicles according to claim 1, wherein: said drive control means (30, 45, 53) comprises: a microcomputer unit (30) which, receiving said output signal (S 1 , S 2 ) from said steering torque detecting means (31), said output signal (S 3 , S 4 ) from said steering speed detecting means (35), and said output signal (dNs) from said steering acceleration detecting means (115, 116, 122-126, 130-132), determines and outputs a motor control signal (T 3 , T 4 ) representing the content of said drive signal (Va) to be given to said electric motor (18); and motor drive means (45) which, receiving said motor control signal (T 3 , T 4 ), gives said motor drive signal (Va) to said electric motor (18) in dependence on said motor control signal (T 3 , T 4 ); and said microcomputer unit (30) is adapted to determine said motor control signal (T 3 , T 4 ) in an address designation manner in dependence on respective said output signals (S 1 , S 2 , S 3 , S 4 and dNs) from respective said detecting means (31, 35, and 115, 116, 122-126, 130-132).
Claim 4
Dependent Claim
191 words
An electric power steering system for vehicles according to claim 2, wherein: said motor drive signal (Va) to be given from said motor drive means (45) to said electric motor (18) is an armature voltage signal (Va); said motor drive means (45) comprises a drive circuit (45) for impressing said armature voltage signal (Va) as a PWM signal to said electric motor (18); said microcomputer unit (30) is adapted to determine: in dependence on said steering torque signal (S 1 , S 2 ) in an address designation manner a duty value [D(Ia·Ra)] attributed to said steering torque (Ts); in dependence on said steering speed signal (S 3 , S 4 ) in an address designation manner a duty value [D(K·Nm)] attributed to said steering speed (Ns); and in dependence on said steering acceleration signal (dNs) in an address designation manner a duty value [(a·J·dw/dt)] attributed to said steering acceleration (dNs); and said microcomputer unit (30) is further adapted for outputting to said drive circuit (45) said motor control signal (T 3 , T 4 ) having as a component thereof the sum of respective said duty values [D(Ia·Ra), D(K·Nm), D(a·J·dw/dt)].
Claim 5
Dependent Claim
54 words
An electric power steering system for vehicles according to claim 1, wherein: said output signal (dNs) from said steering acceleration detecting means (115, 116, 122-126, 130-132) is determined by said drive control means (30, 45) in dependence on said output signal (S 3 , S 4 ) from said steering speed detecting means (35).
Claim 6
Dependent Claim
195 words
An electric power steering system for vehicles according to claim 1, wherein: said drive control means (30, 45, 53) comprises: a control circuit (30) which, receiving said output signal (S 1 , S 2 ) from said steering torque detecting means (31), said output signal (S 3 , S 4 ) from said steering speed detecting means (35), and said output signal (dNs) from said steering acceleration detecting means (115, 116, 122-126, 130-132), determines and outputs a motor control signal (T 3 , T 4 ) representing the content of said drive signal (Va) to be given to said electric motor (18); and a motor drive circuit (45) which, receiving said motor control signal (T 3 , T 4 ), gives said motor drive signal (Va) to said electric motor (18) in dependence on said motor control signal (T 3 , T 4 ); and said control circuit (30) is adapted to determine said motor control signal (T 3 , T 4 ) in dependence on respective said output signals (S 1 , S 2 , S 3 , S 4 and dNs) from respective said detecting means (31, 35, and 115, 116, 122-126, 130-132).
Claim 7
Dependent Claim
173 words
An electric power steering system for vehicles according to claim 5, wherein: said motor drive signal (Va) to be given from said motor drive circuit (45) to said electric motor (18) is an armature voltage signal (Va); said motor drive circuit (45) is adapted for impressing said armature voltage signal (Va) as a PWM signal to said electric motor (18); said control circuit (30) is adapted to determine: in dependence on said steering torque signal (S 1 , S 2 ) a duty value [D(Ia·Ra)] attributed to said steering torque (Ts); in dependence on said steering speed signal (S 3 , S 4 ) a duty value [D(K·Nm)] attributed to said steering speed (Ns); and in dependence on said steering acceleration signal (dNs) a duty value [(a·J·dw/dt)] attributed to said steering acceleration (dNs); and said control circuit (30) is further adapted for outputting to said drive circuit (45) said motor control signal (T 3 , T 4 ) having as a component thereof the sum of respective said duty values [D(Ia·Ra), D(K·Nm), D(a·J·dw/dt)].
Claim 8
Dependent Claim
80 words
An electric power steering system for vehicles according to claim 1, wherein: said motor drive signal (Va) to be given from said motor drive means (30, 45, 53) to said electric motor (18) is an armature voltage signal (Va); and said drive control means (30, 45, 53) includes feedback signal generating means (53) which, detecting an armature current (Ia) of said electric motor (18), gives an output signal (S 5 ) therefrom to said drive control means (30, 45, 53).
Claim 9
Dependent Claim
37 words
An electric power steering system for vehicles according to claim 1, further comprising: a speed reduction mechanism (19) for transmitting torque generated by said electric motor (18) to said output shaft (5) in a speed reducing manner.