US4727950A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric power steering system for vehicles
Assignee: Honda Motor Co Ltd
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Filing: 1987-07-27
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Granted: 1988-03-01
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Expires: 2007-07-27
Abstract
Abstract An electric power steering system (200) for vehicles including a driving control circuit (76, 100, 108) for feeding, in consideration of an output signal (S1, S2) from a steering torque detection 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). In the steering system, the auxiliary torque to be developed at the electric motor (33) is reduced, under the condition that a steering angle (Th) of the steering wheel has exceeded a predetermined angle (Th1).
Inventors
- 👤 Yasuo Shimizu
- 👤 Toshitake Kawai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:23
CPC Classifications
B; B62; B62D; B62D5/00; B62D5/04; B62D5/0457; B62D5/046; B62D5/0469
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
147 words
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; steering torque detection means for detecting steering torque acting on said input shaft; driving control means for feeding said electric motor with a motor drive signal based on an output signal from said steering torque detecting means; steering angle detection means for detecting a steering angle of said steering wheel; and correction means for gradually decreasing said motor drive signal to reduce said auxiliary torque to be developed at said electric motor, when said steering angle of said steering wheel is detected to be exceeding a predetermined angle by said steering angle detection means, said predetermined angle being slightly less than a maximum steering angle of said steering wheel.
Claim 2
Dependent Claim
147 words
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; steering torque detection means for detecting steering torque acting on said input shaft; driving control means for feeding said electric motor with a motor drive signal based on an output signal from said steering torque detecting means; steering angle detection means for detecting a steering angle of said steering wheel; and correction means for gradually decreasing said motor drive signal to reduce said auxiliary torque to be developed at said electric motor, when said steering angle of said steering wheel is detected to be exceeding a predetermined angle by said steering angle detection means, said predetermined angle being slightly less than a maximum steering angle of said steering wheel.
Claim 3
Dependent Claim
41 words
An electric power steering system according to claim 1, wherein: said correction means is for decreasingly correcting said motor drive signal to zero, when said steering angle has exceeded said predetermined angle to thereby stop the operation of said electric motor.
Claim 4
Dependent Claim
60 words
An electric power steering system according to claim 1 wherein: said correction means is for decreasing said motor drive signal finally reducing to zero, as said steering angle is varied from said predetermined angle to said maximum steering angle, to thereby reduce said auxiliary torque to be developed at said electric motor, finally stopping the operation of said electric motor.
Claim 5
Dependent Claim
25 words
An electric power steering system according to claim 3, wherein: said correction means is for operatively and continuously correcting said motor drive signal till zero.
Claim 6
Dependent Claim
32 words
An electric power steering system according to claim 1, wherein: said motor drive signal to be fed from said driving control means to said electric motor (33) comprises an armature voltage signal.
Claim 7
Dependent Claim
53 words
An electric power steering system according to claim 1, further comprising: electromagnetic clutch means for transmitting torque developed at said electric motor to said output shaft and said driving control means for feeding said electromagnetic clutch means with a clutch drive signal based on said output signal from said steering torque detecting means.
Claim 8
Dependent Claim
33 words
An electric power steering system according to claim 6, further comprising: a reduction mechanism for transmitting said torque developed at said electric motor to said electromagnetic clutch means, while reducing the speed thereof.
References Cited (Backward Citations)
DE2056066A1
Cited
FR2240856A1
Cited
JPS5271028A
Cited
JPS57184969A
Cited
JPS58105876A
Cited
JPS5970257A
Cited
GB2145678A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-01 | 1991-08-31 | 1992-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-01 | 1995-08-31 | 1996-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-01 | 1999-08-31 | 2000-03-01 | $7700.00 | Window Closed / Lapsed |