US4930040A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current regulator for inductive loads
Assignee: Wabco Westinghouse Fahrzeugbremsen GmbH
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Filing: 1988-11-14
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Granted: 1990-05-29
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Expires: 2008-11-14
Abstract
Abstract A current regulator for an inductive load especially for a coil of an electromagnetic solenoid valve. The current flow through the coil is regulated and compared by means of an operational amplifying nominal current value. The inductive load comparator is initially controlled by a first conductive diode. A second diode having a higher voltage rating than that of the first diode is rendered conductive whenever the nominal current value in an inductive coil decreases rapidly. The current regulator ensures that the magnetic energy in the inductive load remains unchanged when the nominal current value remains constant or changes in small amounts. When a rapid decrease of the coil current occurs, the second diode is rendered conductive.
Inventors
- 👤 Jurgen Binarsch
- 👤 Jurgen Bode
- 👤 Lutz Danne
- 👤 Norbert Lissel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:14
CPC Classifications
H; H01; H01H; H01H47/00; H01H47/22; H01H47/32; H01H47/325; H02; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156; H02M3/158
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
120 words
A current controller for supplying current to an inductive load, such as, an electromagnetic coil of a solenoid comprising, a first comparator means connected to said electromagnetic coil for regulating the current supplied to said electromagnetic coil to a desired nominal value, a first switch means connected to said first comparator means and being turned ON and OFF by said first comparator means to cause voltage pulses to be conveyed to said electromagnetic coil, and a second comparator means connected to a second switch means which causes a first recovery diode to be connected to said electromagnetic coil during minute current changes and which causes a second recover diode to be connected to said electromagnetic coil during dramatic current changes.
Claim 2
Dependent Claim
120 words
A current controller for supplying current to an inductive load, such as, an electromagnetic coil of a solenoid comprising, a first comparator means connected to said electromagnetic coil for regulating the current supplied to said electromagnetic coil to a desired nominal value, a first switch means connected to said first comparator means and being turned ON and OFF by said first comparator means to cause voltage pulses to be conveyed to said electromagnetic coil, and a second comparator means connected to a second switch means which causes a first recovery diode to be connected to said electromagnetic coil during minute current changes and which causes a second recover diode to be connected to said electromagnetic coil during dramatic current changes.
Claim 3
Dependent Claim
23 words
The current controller, as defined in claim 1, wherein said second recovery diode has a higher forward voltage than said first recovery diode.
Claim 4
Dependent Claim
17 words
The current controller, as defined in claim 1, wherein said second recovery diode is a Zener diode.
Claim 5
Dependent Claim
22 words
The current controller, as defined in claim 1, wherein said first comparator means takes the form of an integrated circuit operational amplifier.
Claim 6
Dependent Claim
21 words
The current controller, as defined in 1, wherein said second comparator means takes the form of an integrated circuit operational amplifier.
Claim 7
Dependent Claim
21 words
The current controller, as defined in 1, wherein said second comparator means takes the form of an integrated circuit operational amplifier.
Claim 8
Dependent Claim
20 words
The current controller, as defined in claim 1, wherein a precision resistor is connected in series with said electromagnetic coil.
Claim 9
Dependent Claim
17 words
The current controller, as defined in claim 1, wherein said first switching means is a power transistor.
Claim 10
Dependent Claim
16 words
The current controller, as defined in claim 7, wherein said power transistor is a PNP transistor.
Claim 11
Dependent Claim
19 words
The current controller, as defined in claim 1, wherein said second switching means is an electronic reversing switching circuit.
Claim 12
Dependent Claim
24 words
The current controller, as defined in claim 9, wherein said electronic reversing switching circuit includes a pair of transistors and a plurality of resistors.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-28 | 1993-11-27 | 1994-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-28 | 1997-11-27 | 1998-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-28 | 2001-11-27 | 2002-05-29 | $7700.00 | Window Closed / Lapsed |