US5698956A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for electrically operated power steering apparatus
Assignee: Mitsubishi Electric Corp
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Filing: 1996-01-03
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Granted: 1997-12-16
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Expires: 2016-01-03
Abstract
Abstract A control system for an electrically operated power steering apparatus which is capable of eliminating an incongruous steering sensation and improving the converging performance of a steering wheel. The control system comprises a steering torque detecting unit 20 for detecting a steering torque applied to a steering system, a motor 10 coupled to the steering system, and a control unit for controlling the motor 10 using an output of the steering torque detecting unit 20 phase-compensated on the basis of a speed of the motor 10. The control unit includes a target current determining section 25 for determining a target current to the motor 10 on the basis of the output of the steering torque detecting unit 20 and a phase compensating section 21 for obtaining a phase compensation value on the basis of the output of the steering torque detecting unit 20 and the speed of the motor 10. The target current is corrected by the phase compensation value.
Inventors
- 👤 Kazuhisa Nishino
- 👤 Hirohisa Awa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 10:06
CPC Classifications
B; B62; B62D; B62D6/00; B62D5/00; B62D5/04; B62D5/0457; B62D5/046; B62D5/0463
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
130 words
A control system for an electrically operated power steering apparatus, comprising: steering torque detecting means for detecting a steering torque applied to a steering system; a motor coupled to said steering system; target current determining means for determining a target current to be supplied to said motor on the basis of an output of said steering torque detecting means; a motor speed sensor; phase compensating means for obtaining a phase compensation value on the basis of said output of said steering torque detecting means and rotational speed of said motor detected by said motor speed sensor; correcting circuit for correcting said target current in accordance with said phase compensation value and outputting a corrected target current; and motor output means for driving said motor according to the corrected target current.
Claim 2
Dependent Claim
130 words
A control system for an electrically operated power steering apparatus, comprising: steering torque detecting means for detecting a steering torque applied to a steering system; a motor coupled to said steering system; target current determining means for determining a target current to be supplied to said motor on the basis of an output of said steering torque detecting means; a motor speed sensor; phase compensating means for obtaining a phase compensation value on the basis of said output of said steering torque detecting means and rotational speed of said motor detected by said motor speed sensor; correcting circuit for correcting said target current in accordance with said phase compensation value and outputting a corrected target current; and motor output means for driving said motor according to the corrected target current.
Claim 3
Dependent Claim
84 words
A control system as defined in claim 1, wherein said phase compensating means includes: phase compensation calculating means for calculating said phase compensation value as a function of a variation of said output of said steering torque detecting means and a predetermined coefficient; and gain multiplication means for determining a torque compensation output by multiplying a gain factor, determined in accordance with said motor speed, by the phase compensation value, wherein said correcting circuit corrects said target current according to said torque compensation output.
Claim 4
Dependent Claim
28 words
A control system as defined in claim 2, wherein limitation is imposed on at least one of said gain factor and an output of said phase compensating means.
Claim 5
Dependent Claim
16 words
A control system as defined in claim 3, wherein a hysteresis is factored into the limitation.
Claim 6
Dependent Claim
16 words
A control system as defined in claim 2, wherein said gain factor takes on negative values.
Claim 7
Dependent Claim
31 words
A control system as defined in claim 1, further comprising a phase compensation output limiting means for limiting an output of said phase compensating means in accordance with said motor speed.
Claim 8
Dependent Claim
54 words
A control system as defined in claim 1, wherein said phase compensating means is composed of phase compensation calculating means for phase-compensating for said output of said steering torque detecting means as a function of an operation coefficient, and said phase compensating means determines said operation coefficient on the basis of said motor speed.
Claim 9
Dependent Claim
94 words
A control system as defined in claim 1, further comprising: speed maintaining means for storing a maximum value of said motor speed when said motor speed exceeds a first decision value; and clearing means for clearing the maximum value of said motor speed stored in the speed maintaining means in response to the occurrence of at least one of said motor speed dropping below a second decision value smaller than said first decision value and the polarity of said motor speed reverses, the stored maximum value being used for control by said control system.
Claim 10
Dependent Claim
58 words
A control system as defined in claim 1, further comprising a subtraction circuit receiving the corrected target current, reducing the corrected target current by an amount corresponding to electric current of said motor, and providing a reduced target current to said motor output means, wherein said motor output means drives said motor according to the reduced target current.
References Cited (Backward Citations)
US4800975A
Cited
JPS6234856A
Cited
US4830137A
Cited
US4979114A
Cited
DE3917053A1
Cited
US5040629A
Cited
US5201818A
Cited
US5469357A
Cited
US5404960A
Cited
US5504679A
Cited
US5480000A
Cited
US5507359A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-12-15 | 2001-06-16 | 2001-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-12-15 | 2005-06-16 | 2005-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-12-15 | 2009-06-16 | 2009-12-16 | $7700.00 | Window Closed / Lapsed |