Patent US2798486A successfully refreshed from Google Patents.
Patent US3579052A successfully refreshed from Google Patents.
US3579052A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for driving a. d. c. electromagnet
Assignee: Denso Corp
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Filing: 1969-08-05
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Granted: 1971-05-18
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Expires: 1989-08-05
Abstract
Abstract A system for driving a DC electromagnet of the kind in which an armature is attracted by the magnetic action of current supplied to an electromagnetic winding, having an attraction starting circuit for generating a DC voltage for a predetermined period of time for completing the attraction of the armature, and an attraction-holding circuit for generating an intermittent voltage. After the voltage generated by the attraction starting circuit is applied to the electromagnetic winding to complete the voltage attraction of the armature, the intermittent voltage generated by the attraction holding circuit is solely applied to the electromagnetic winding for holding the armature in its attracted state. Thus, a large force of attraction is produced by a DC electromagnet having a small physical constitution and heat generated therein can be reduced.
Inventors
- 👤 Takaaki Kato
- 👤 Mamoru Kawakubo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:31
CPC Classifications
H; H01; H01H; H01H47/00; H01H47/22; H01H47/32; H01H47/325
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
167 words
A system for driving a DC electromagnet of the kind in which an armature is attracted by the magnetic action of a current supplied to an electromagnetic winding, said system comprising output terminal means adapted to be connected to said winding, attraction-starting circuit means connected to said terminal means for generating a DC voltage continuously for a predetermined period of time, attraction holding circuit means connected to said terminal means for generating an intermittent voltage, and means, including a connection between aid starting and holding circuit means, for mutually exclusively applying said DC and intermittent voltages in that order to said output terminal, the arrangement being such that upon connection of the output terminal means to said winding, the DC voltage generated by said attraction-starting circuit means is first applied to the electromagnetic winding to effect the attraction of the armature, after which the intermittent voltage generated by said attraction-holding circuit means is solely applied to the electromagnetic winding for holding the armature in its attracted state.
Claim 2
Independent Claim
167 words
A system for driving a DC electromagnet of the kind in which an armature is attracted by the magnetic action of a current supplied to an electromagnetic winding, said system comprising output terminal means adapted to be connected to said winding, attraction-starting circuit means connected to said terminal means for generating a DC voltage continuously for a predetermined period of time, attraction holding circuit means connected to said terminal means for generating an intermittent voltage, and means, including a connection between aid starting and holding circuit means, for mutually exclusively applying said DC and intermittent voltages in that order to said output terminal, the arrangement being such that upon connection of the output terminal means to said winding, the DC voltage generated by said attraction-starting circuit means is first applied to the electromagnetic winding to effect the attraction of the armature, after which the intermittent voltage generated by said attraction-holding circuit means is solely applied to the electromagnetic winding for holding the armature in its attracted state.
Claim 3
Dependent Claim
72 words
A system as in claim 1 including input terminal means connected commonly to said starting and holding circuit means for receiving a common trigger signal by which said circuit start to operate simultaneously, said connection between said starting and holding circuit means being such that the said intermittent voltage is suppressed and not applied to said output terminal means while said DC voltage is generated and applied thereto during said predetermined time.
Claim 4
Dependent Claim
53 words
A system as in claim 2 wherein each of said starting and holding circuit means includes a respective output valve referenced to a predetermined level of voltage so that when said starting circuit means is generating said DC voltage its output valve effectively shorts the said intermittent voltage to said predetermined voltage level.
Claim 5
Dependent Claim
53 words
A system as in claim 1 wherein said output terminal means includes two terminals and said system further includes means connected across said terminals for causing the current flowing through said winding, when the output terminals are connected thereto, to be continuous while the voltage causing that current is the aforesaid intermittent voltage.
Claim 6
Dependent Claim
14 words
A system as in claim 4 wherein said continuous current-causing means includes a diode.
Claim 7
Dependent Claim
93 words
A system as in claim 1 wherein said attraction-starting circuit means includes a monostable multivibrator and a switching element connected between said multivibrator and said output terminal means to control the application of voltage thereto in response to operation of said multivibrator, said attraction-holding circuit means including an astable multivibrator and a second switching element connected between said astable multivibrator and said output terminal means for switchIng voltage thereto in response to operation of said astable multivibrator in the absence of switching by said first-mentioned switching element of voltage from said monostable multivibrator.
Claim 8
Dependent Claim
27 words
A system as in claim 1 including in combination therewith the said electromagnet and its winding and armature, said winding being connected across said output terminal means.
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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) | 1974-05-17 | 1974-11-16 | 1975-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-17 | 1978-11-16 | 1979-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-17 | 1982-11-16 | 1983-05-18 | $7700.00 | Window Closed / Lapsed |