US5600559A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric power steering apparatus
Assignee: Koyo Seiko Co Ltd
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Filing: 1996-04-26
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Granted: 1997-02-04
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Expires: 2016-04-26
Abstract
Abstract The present invention provides an electric power steering apparatus in which it is decided whether or not steering torque is in a predetermined drive inhibition area, and when the term in which the decision result is logically inconsistent with driving instruction for the motor in accordance with the steering torque is shorter than a predetermined period of time, a timer is reset to drive the motor. As a result, the compensation of the inertia of said motor can be controlled even when the steering torque is small. Further, in the electric power steering apparatus, the timer is also reset to drive the motor when the steering torque is in a dead zone and a driving current for the motor is smaller than a predetermined value. As a result, the drive of the motor can be controlled also when a steering wheel is returned to its initial position.
Inventors
- 👤 Mitsuhiko Nishimoto
- 👤 Hirofumi Matsuoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:55
CPC Classifications
B; B62; B62D; B62D5/00; B62D5/04; B62D5/0457; B62D5/046; B62D5/0466; B62D5/0481; B62D5/0493
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
211 words
An electric power steering apparatus, comprising: a torque sensor for detecting steering torque; a data processor for generating a control signal for driving a motor corresponding to a value obtained by adding a target value in accordance with the steering torque detected by said torque sensor and a differentiated value of the steering torque detected by said torque sensor; inhibition zone decision means for deciding whether or not the steering torque detected by said torque sensor is in a predetermined driving direction inhibition zone; consistency verification means for verifying logical consistency or determining inconsistency between a result of a decision by said inhibition zone decision means and the motor control signal generated by said data processor; a timer to time the period during which a result of verification by said consistency verification means is determined as being inconsistent; drive inhibition means for inhibiting drive of said motor at a predetermined time set to occur after the time that the signal of said differentiated value of the steering torque disappears as timed by said timer; and means for inhibiting re-drive of said motor until the control signal for driving said motor disappears upon a predetermined period of time passing after the drive of said motor is inhibited by said drive inhibition means.
Claim 2
Dependent Claim
211 words
An electric power steering apparatus, comprising: a torque sensor for detecting steering torque; a data processor for generating a control signal for driving a motor corresponding to a value obtained by adding a target value in accordance with the steering torque detected by said torque sensor and a differentiated value of the steering torque detected by said torque sensor; inhibition zone decision means for deciding whether or not the steering torque detected by said torque sensor is in a predetermined driving direction inhibition zone; consistency verification means for verifying logical consistency or determining inconsistency between a result of a decision by said inhibition zone decision means and the motor control signal generated by said data processor; a timer to time the period during which a result of verification by said consistency verification means is determined as being inconsistent; drive inhibition means for inhibiting drive of said motor at a predetermined time set to occur after the time that the signal of said differentiated value of the steering torque disappears as timed by said timer; and means for inhibiting re-drive of said motor until the control signal for driving said motor disappears upon a predetermined period of time passing after the drive of said motor is inhibited by said drive inhibition means.
Claim 3
Dependent Claim
123 words
An electric power steering apparatus according to claim 1 wherein said torque sensor detects steering torque corresponding to movement of a steering wheel relative to an initial position, and further comprising: dead zone detection means for detecting whether or not the steering torque detected by said torque sensor is in a dead zone in which torque is approximately zero; driving current detection means for detecting a driving current of said motor; and means for resetting said timer when the driving current detected by said driving current detection means is below a predetermined value equivalent to a current value required when the steering wheel is returned to the initial position and the steering torque detected by said torque sensor is in the dead zone.
References Cited (Backward Citations)
US4629952A
Cited
US4800975A
Cited
US4688655A
Cited
EP0336682A2
Cited
US4896735A
Cited
EP0340044A2
Cited
US4957182A
Cited
US5097918A
Cited
US5253725A
Cited
US5194794A
Cited
US5355315A
Cited
EP0535422A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-02-04 | 2000-08-05 | 2001-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-02-04 | 2004-08-05 | 2005-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-02-04 | 2008-08-05 | 2009-02-04 | $7700.00 | Window Closed / Lapsed |