US5198738A
Expired / Lapsed
US
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Method of determining the rotational speed of a brushless dc-motor
Assignee: Heidelberger Druckmaschinen AG
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Filing: 1991-10-30
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Granted: 1993-03-30
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Expires: 2011-10-30
Abstract
Abstract A method of determining the rotational speed of a three-phase brushless DC-motor, which comprises scanning at least one signal trace disposed on a revolving rotor of a three-phase brushless DC-motor by means of three sensors, each emitting a signal having two possible signal states, the signal trace and the sensors being of such construction and arrangement that eight values are realized by a logical combination of the two possible signal states, respectively, of the three sensors; detecting the rotor position with six of the values; and determining the rotational speed with the other two values.
Inventors
- 👤 Peter T. Blaser
- 👤 Michael Kruger
- 👤 Jurgen Maass
- 👤 Helmut Meyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:15
CPC Classifications
H; H02; H02K; H02K29/00; H02K29/14; G; G01; G01P; G01P3/00; G01P3/42; G01P3/44; G01P3/48; G01P3/481; G01P3/486; G01P3/489; H02K29/06; H02K29/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
98 words
Method of determining the rotational speed of a three-phase brushless DC-motor, which comprises the steps of scanning at least one signal trace disposed on a revolving rotor of a three-phase brushless DC-motor by means of three sensors, each sensor emitting a signal having two possible signal states, the signal trace and the sensors being of such construction and arrangement that .eight values are generated by a logical combination of two possible signal states, respectively, of the three sensors; detecting the rotor position with six of the values; and determining the rotor rotational speed with the other two values.
Claim 2
Dependent Claim
98 words
Method of determining the rotational speed of a three-phase brushless DC-motor, which comprises the steps of scanning at least one signal trace disposed on a revolving rotor of a three-phase brushless DC-motor by means of three sensors, each sensor emitting a signal having two possible signal states, the signal trace and the sensors being of such construction and arrangement that .eight values are generated by a logical combination of two possible signal states, respectively, of the three sensors; detecting the rotor position with six of the values; and determining the rotor rotational speed with the other two values.
Claim 3
Dependent Claim
41 words
Method according to claim 1, wherein the other two values appear as a uniform pulse sequence during a revolution of the rotor, and the steps of determining of the rotor speed includes counting the pulse during one revolution of the rotor.
Claim 4
Dependent Claim
36 words
Method according to claim 1, wherein the other two values appear as a uniform pulse sequence during a revolution of the rotor, and the step of determining of the rotor speed includes measuring the pulse duration.
Claim 5
Dependent Claim
24 words
Method according to claim 1, which includes the step of fading out the other two values in an upper range of the rotor speed.
Claim 6
Dependent Claim
43 words
Method according to claim 1, which further comprises the steps of selecting from the three sensor signals two thereof having a like signal state, and detecting the rotor position when the signal state of one of the two selected sensor signals is changed.
Claim 7
Dependent Claim
108 words
Method of determining the rotational speed of a three phase brushless DC-motor, which comprises the steps of scanning three signal traces disposed on a revolving rotor of a three-phase brushless DC-motor by means of three sensors, each emitting a signal having two possible signal states, the signal traces and the sensors being of such construction and arrangement that eight values are generated by a logical combination of the two possible signal states, respectively, of the three sensors; detecting the rotor position by a combination of pairs of sequential values; and determining the rotor rotational speed by the number of value changes occurring during one revolution of the rotor.
Claim 8
Dependent Claim
108 words
Method of determining the rotational speed of a three phase brushless DC-motor, which comprises the steps of scanning three signal traces disposed on a revolving rotor of a three-phase brushless DC-motor by means of three sensors, each emitting a signal having two possible signal states, the signal traces and the sensors being of such construction and arrangement that eight values are generated by a logical combination of the two possible signal states, respectively, of the three sensors; detecting the rotor position by a combination of pairs of sequential values; and determining the rotor rotational speed by the number of value changes occurring during one revolution of the rotor.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-03-29 | 1996-09-28 | 1997-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-03-29 | 2000-09-28 | 2001-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-03-29 | 2004-09-28 | 2005-03-30 | $7700.00 | Window Closed / Lapsed |