Patent US3845268A successfully refreshed from Google Patents.
US3845268A
Expired / Lapsed
US
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Induction heater apparatus and system
Assignee: Boeing Co
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Filing: 1973-02-12
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Granted: 1974-10-29
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Expires: 1993-02-12
Abstract
Abstract A system for utilizing electrical energy to induce eddy currents in an electrically conductive article, e.g., the metallic member of a hot melt type fastener. An ultrasonic frequency generator circuit utilizing a single SCR and having a maximum power output of about 1 kilowatt includes in circuit therewith a coupling coil for providing directly a high concentrated magnetic field which induces eddy currents in the electrically conductive article for rapid heating.
Inventors
- 👤 M Sindt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:12
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/523; B; B29; B29C; B29C65/00; B29C65/02; B29C65/34; B29C65/36; B29C65/3604; B29C65/3644; B29C65/3672; B29C65/3676; B29C65/368; B29C65/44; B29C65/46; B29C65/48; B29C65/4805; B29C65/481; B29C65/4815; B29C65/50; B29C65/5057; B29C66/00; B29C66/01; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/1122; B29C66/20; B29C66/21; B29C66/40; B29C66/41; B29C66/43; B29C66/45; B29C66/47; B29C66/472; B29C66/70; B29C66/72; B29C66/725; B29C66/7252; B29C66/72525; B29C66/74; B29C66/742; B29C66/80; B29C66/81; B29C66/818; B29C66/8181; B29C66/81811; B29C66/84; B29C66/861; B29C66/452; B29C66/81812; B29C66/83; B29C66/832; B29C66/8322
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
196 words
In combination in an apparatus for producing induction heating: an ultrasonic frequency current generator (24) for generating ultrasonic frequency current at a frequency above about 25 kilohertz and having first (603) and second (691) input terminals and first capacitance means (605) coupled between said terminals; a D.C. voltage source; first means for coupling said D.C. voltage source between said first (603) and second (691) input terminals; a first series circuit path coupled between said first (603) and second (691) input terminals, said first series circuit path comprising a silicon controlled rectifier (601), second capacitance means (983, 984) and a primary coil (30) of an air core transformer; said air core transformer having a disk like secondary (32); a pulse generator coupled to the gate electrode (94) of said silicon controlled rectifier (601); a second series circuit path coupled across said second capacitance means, said second series circuit path comprising a first diode (868) and a first inductor (777); a third series circuit path coupled across said silicon controlled rectifier (601), said third series path comprising a first resistance means (650) and third capacitance means (989); and a second diode (867) connected across said silicon controlled rectifier.
Claim 2
Dependent Claim
196 words
In combination in an apparatus for producing induction heating: an ultrasonic frequency current generator (24) for generating ultrasonic frequency current at a frequency above about 25 kilohertz and having first (603) and second (691) input terminals and first capacitance means (605) coupled between said terminals; a D.C. voltage source; first means for coupling said D.C. voltage source between said first (603) and second (691) input terminals; a first series circuit path coupled between said first (603) and second (691) input terminals, said first series circuit path comprising a silicon controlled rectifier (601), second capacitance means (983, 984) and a primary coil (30) of an air core transformer; said air core transformer having a disk like secondary (32); a pulse generator coupled to the gate electrode (94) of said silicon controlled rectifier (601); a second series circuit path coupled across said second capacitance means, said second series circuit path comprising a first diode (868) and a first inductor (777); a third series circuit path coupled across said silicon controlled rectifier (601), said third series path comprising a first resistance means (650) and third capacitance means (989); and a second diode (867) connected across said silicon controlled rectifier.
Claim 3
Dependent Claim
234 words
In combination: an ultrasonic frequency current generator for generating ultrasonic frequency current at a frequency higher than about 25 kilohertz, said generator having first and second input terminals and first capacitance means coupled between said terminals; a D.C. voltage source; first means for coupling said D.C. voltage source between said first and second input terminals; a first series circuit path coupled between said first and second input terminals, said first series path comprising a silicon controlled rectifier, second capacitance means and a primary coil of an air core transformer disposed in an air-cooled housing; said air core transformer having a secondary comprising a metal disk-like member, said primary coil having a diameter equal to or greater than the diameter of said disk-like member; a pulse generator coupled to the gate electrode of said silicon controlled rectifier; a second series circuit path coupled across said second capacitance means, said second series path comprising a first diode and a first inductor; a second diode connected across said silicon controlled rectifier; said first means including a timing circuit for connecting said D.C. voltage source between said first and second terminals for a predetermined time period less than about 30 seconds, and switching means for energizing said timing circuit; said switching means arranged in said air cooled housing; and said timing circuit including alarm means for providing an audible alarm at the end of said predetermined time period.
Claim 4
Dependent Claim
234 words
In combination: an ultrasonic frequency current generator for generating ultrasonic frequency current at a frequency higher than about 25 kilohertz, said generator having first and second input terminals and first capacitance means coupled between said terminals; a D.C. voltage source; first means for coupling said D.C. voltage source between said first and second input terminals; a first series circuit path coupled between said first and second input terminals, said first series path comprising a silicon controlled rectifier, second capacitance means and a primary coil of an air core transformer disposed in an air-cooled housing; said air core transformer having a secondary comprising a metal disk-like member, said primary coil having a diameter equal to or greater than the diameter of said disk-like member; a pulse generator coupled to the gate electrode of said silicon controlled rectifier; a second series circuit path coupled across said second capacitance means, said second series path comprising a first diode and a first inductor; a second diode connected across said silicon controlled rectifier; said first means including a timing circuit for connecting said D.C. voltage source between said first and second terminals for a predetermined time period less than about 30 seconds, and switching means for energizing said timing circuit; said switching means arranged in said air cooled housing; and said timing circuit including alarm means for providing an audible alarm at the end of said predetermined time period.
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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) | 1977-10-28 | 1978-04-29 | 1978-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-28 | 1982-04-29 | 1982-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-28 | 1986-04-29 | 1986-10-29 | $7700.00 | Window Closed / Lapsed |