US3736467A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reed relay circuit for controlling inductive loads
Assignee: International Business Machines Corp
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Filing: 1971-08-13
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Granted: 1973-05-29
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Expires: 1991-08-13
Abstract
Abstract A reed relay circuit may be utilized to govern highly inductive loads without destructive arcing at the reed relay contacts by governing the relay in such manner than an auxiliary flux field is supplied by rectification of the current to the load, which provides an auxiliary field in which the current and the flux decay to zero at least once during each cycle. When the controlling flux is removed, the reed relay contacts will not open until the auxiliary flux decreases to a point at which its generating current is sufficiently low that adverse arcing and other current effects at the contacts are eliminated.
Inventors
- 👤 H Meier
- 👤 J Yarrington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:24
CPC Classifications
H; H01; H01H; H01H36/00; H01H36/0006; H01H9/00; H01H9/54; H01H9/56
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
171 words
Switching apparatus for selective connection of a source of alternating current to a load, comprising, in combination, a reed switch having contacts which are closed when influenced by a magnetic field greater than a first predetermined value, and open when influenced by a magnetic field less than a second predetermined value, said contacts being connected to said source by a series circuit including said load, control means for selectively supplying a magnetic field greater than said first predetermined value to thereby close said contacts and energize said load and auxiliary magnetizing means for generating a fluctuating magnetic field having a maximum amplitude greater than said second value, to thereby retain said contacts closed when said auxiliary magnetizing means is effective, said auxiliary magnetizing means comprising a winding and a unidirectional conductive device connected so that current to said load flows through said winding and said unidirectional conductive device to produce a fluctuating magnetic field which approaches or reaches a zero value at least once during each cycle of said alternating current.
Claim 2
Dependent Claim
171 words
Switching apparatus for selective connection of a source of alternating current to a load, comprising, in combination, a reed switch having contacts which are closed when influenced by a magnetic field greater than a first predetermined value, and open when influenced by a magnetic field less than a second predetermined value, said contacts being connected to said source by a series circuit including said load, control means for selectively supplying a magnetic field greater than said first predetermined value to thereby close said contacts and energize said load and auxiliary magnetizing means for generating a fluctuating magnetic field having a maximum amplitude greater than said second value, to thereby retain said contacts closed when said auxiliary magnetizing means is effective, said auxiliary magnetizing means comprising a winding and a unidirectional conductive device connected so that current to said load flows through said winding and said unidirectional conductive device to produce a fluctuating magnetic field which approaches or reaches a zero value at least once during each cycle of said alternating current.
Claim 3
Dependent Claim
47 words
The combination as claimed in claim 1, in which said control means comprises a movable magnet, movable between a first position in which it supplies a field greater than said first value and a second position in which it supplies a field less than said second value.
Claim 4
Dependent Claim
15 words
The combination as claimed in claim 2, in which said magnet is a permanent magnet.
Claim 5
Dependent Claim
32 words
The combination as claimed in claim 1, in which said control means comprises a control winding and means to energize said winding to selectively produce a field greater than said first value.
Claim 6
Dependent Claim
27 words
The combination as claimed in claim 1, in which bias magnetizing means are provided for supplying a bias field having a value less than said second value.
Claim 7
Dependent Claim
33 words
The combination as claimed in claim 1, in which said winding is center-tapped and diodes are connected in series with said winding at each end terminal thereof to provide a full-wave rectifier combination.
Claim 8
Dependent Claim
28 words
The combination as claimed in claim 1, in which pairs of oppositely poled diodes are connected to each end of said winding in a full-wave bridge rectifier configuration.
Claim 9
Dependent Claim
23 words
The combination as claimed in claim 4, in which means are provided for supplying a small steady bias current to said control winding.
References Cited (Backward Citations)
US3348121A
Cited
US3319128A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-28 | 1976-11-27 | 1977-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-28 | 1980-11-27 | 1981-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-28 | 1984-11-27 | 1985-05-29 | $7700.00 | Window Closed / Lapsed |