Patent US4473782A successfully refreshed from Google Patents.
US4473782A
Expired / Lapsed
US
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Drive circuit for brushless direct-current motors
Assignee: Ebm Papst Mulfingen GmbH and Co KGaA and Co KG
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Filing: 1983-01-26
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Granted: 1984-09-25
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Expires: 2003-01-26
Abstract
Abstract A drive circuit for brushless direct-current motors having a cylinder-like air gap between a permanent magnetic inner or outer rotor and a stator, the stator windings being connected to a supply direct-current source in series with a respective feed transistor. The current flux depends on position signals from a semiconductor control element determining the rotor position, in particular a Hall IC, and on the switching state of a semiconductor switch responding to blocking of the rotor and serving as blocking protection for the stator windings. In order to avoid a thermal overload of the stator windings and of the semiconductor elements contained in the circuit, the semiconductor switch provided as the blocking protection is a transistor. The emitter/collector path of the blocking protection transistor is in series with the stator windings and the feed transistors associated with each of these stator windings, and the base of the blocking protection transistor receives an inductive voltage generated in the stator windings.
Inventors
- 👤 Wilhelm Reinhardt
- 👤 Helmut Lipp
- 👤 Friedrich O. U. Rudele
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:41
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/08; H03K17/082; H03K17/0826; H02; H02H; H02H7/00; H02H7/08; H02H7/093; H02P; H02P6/00; H02P6/24; H03K2017/0806
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
129 words
A drive circuit for brushless direct-current motors having a cylinder-like air gap between a permanent magnetic inner or outer rotor and a stator, said drive circuit comprising stator windings connected to a supply direct-current source in series with respective feed transistors, in which current flux depends on position signals from a semiconductor control element determining the rotor setting, and on switching state of semiconductor switch means responding to blocking of the rotor and serving as blocking protection for said stator windings, said semiconductors switch means including a blocking protection transistor having an emitter/collector path in series with said stator windings and said feed transistors respectively associated with each of said stator windings, said blocking protection transistor having a base for receiving an inductive voltage generated in said stator windings.
Claim 2
Dependent Claim
129 words
A drive circuit for brushless direct-current motors having a cylinder-like air gap between a permanent magnetic inner or outer rotor and a stator, said drive circuit comprising stator windings connected to a supply direct-current source in series with respective feed transistors, in which current flux depends on position signals from a semiconductor control element determining the rotor setting, and on switching state of semiconductor switch means responding to blocking of the rotor and serving as blocking protection for said stator windings, said semiconductors switch means including a blocking protection transistor having an emitter/collector path in series with said stator windings and said feed transistors respectively associated with each of said stator windings, said blocking protection transistor having a base for receiving an inductive voltage generated in said stator windings.
Claim 3
Dependent Claim
32 words
A drive circuit according to claim 1, wherein said base of said blocking protection transistor is connected to one end of each stator winding through a respective diode for each stator winding.
Claim 4
Dependent Claim
24 words
A drive circuit according to claim 2, wherein said base of said blocking protection transistor is connected to each diode through a common resistor.
Claim 5
Dependent Claim
53 words
A drive circuit according to claim 3, wherein said base of said blocking protection transistor is connected to one terminal of said supply direct-control source through an emitter/collector path of a starting transistor, said starting transistor having a base connected through an RC circuit to the other terminal of said supply direct-current source.
Claim 6
Dependent Claim
37 words
A drive circuit according to claim 4, including two stator windings, said feed transistor associated with one of said stator windings being connected through a transistor acting as inverter to an output of said semiconductor control element.
Claim 7
Dependent Claim
53 words
A drive circuit according to claim 1, wherein said base of said blocking protection transistor is connected to one terminal of said supply direct-current source through an emitter/collector path of a starting transistor, said starting transistor having a base connected through an RC circuit to the other terminal of said supply direct-current source.
Claim 8
Dependent Claim
38 words
A drive circuit according to claim 1, including two stator windings, said feed transistor associated with one of said stator windings being connected through a transistor acting as an inverter to an output of said semiconductor control element.
References Cited (Backward Citations)
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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) | 1987-09-25 | 1988-03-26 | 1988-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-25 | 1992-03-26 | 1992-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-25 | 1996-03-26 | 1996-09-25 | $7700.00 | Window Closed / Lapsed |