US3840774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetron operating circuit with surge-voltage absorber
Assignee: New Nippon Electric Co Ltd
•
Filing: 1973-02-15
•
Granted: 1974-10-08
•
Expires: 1993-02-15
Abstract
Abstract In an operating circuit for energizing a magnetron by the use of a high-voltage transformer, a surge-voltage absorber is provided to protect components in the high-voltage circuit from the damage due to abnormal voltage induced in the high-voltage transformer particularly during the unstable operation of the magnetron such as warming-up time. The operating circuit includes a high voltage transformer, preferably of constant current type having the primary winding coupled to an A.C. source and the secondary winding coupled in parallel to a uni-directional conducting device, and both of the magnetron and the surge-voltage absorber. The surge-voltage absorber comprises charging and discharging means consisted of a capacitor and a resistor, and a series connected rectifier of which the polarity is the same with that of the magnetron. Preferably, the uni-directional conducting device is a half-wave rectifier being poled oppositely to the surge-voltage absorber and a capacitor in series to the secondary winding so as to absorb the abnormal voltages mainly produced in the warm-up period of the magnetron.
Inventors
- 👤 K Iwata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:10
CPC Classifications
H; H05; H05B; H05B6/00; H05B6/64; H05B6/66; H05B6/666; H02; H02H; H02H7/00; H02H7/20; H02H9/00; H02H9/04; H03; H03B; H03B9/00; H03B9/01; H03B9/10
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
122 words
An operating circuit for energizing a magnetron from an a.c. power source which comprises: a. a magnetron having an anode and a cathode, b. a high voltage transformer having a primary winding connected to said a.c. power source and a secondary winding connected to said magnetron, c. a uni-directional conducting device coupled to said magnetron and poled oppositely to said magnetron so as to allow the flow of current through the magnetron for alternate half-cycles of said a.c. power source, and d. a surge-voltage absorber connected in the parallel relation with said magnetron and comprising a series circuit of a rectifier and charging-discharging means, wherein said absorber serves to protect components of the high voltage operating circuit from abnormal voltage produced therein.
Claim 2
Dependent Claim
122 words
An operating circuit for energizing a magnetron from an a.c. power source which comprises: a. a magnetron having an anode and a cathode, b. a high voltage transformer having a primary winding connected to said a.c. power source and a secondary winding connected to said magnetron, c. a uni-directional conducting device coupled to said magnetron and poled oppositely to said magnetron so as to allow the flow of current through the magnetron for alternate half-cycles of said a.c. power source, and d. a surge-voltage absorber connected in the parallel relation with said magnetron and comprising a series circuit of a rectifier and charging-discharging means, wherein said absorber serves to protect components of the high voltage operating circuit from abnormal voltage produced therein.
Claim 3
Dependent Claim
24 words
The operating circuit as claimed in claim 1, wherein said charging-discharging means is a parallel circuit of a by-pass capacitor and a discharging resistor.
Claim 4
Dependent Claim
38 words
The operating circuit as claimed in claim 2, wherein said uni-directional conducting device is a half-wave rectifier, and further comprising a series capacitor connected between one terminal of said secondary winding and one electrode of said half-wave rectifier.
Claim 5
Dependent Claim
26 words
The operating circuit as claimed in claim 3, wherein said high voltage transformer is a leakage transformer so that the magnetron operates with a constant current.
Claim 6
Dependent Claim
37 words
The magnetron operating circuit as claimed in claim 3, wherein said surge-voltage absorber is connected across the terminals of said secondary winding of said high-voltage transformer, whereby the rated maximum withstanding voltage of said absorber is reduced.
Claim 7
Dependent Claim
29 words
The operating circuit as claimed in claim 1, further comprising a resistor connected across said uni-directional conducting device so as to discharge electric charges remaining in the operating circuits.
Claim 8
Dependent Claim
141 words
A magnetron operating circuit comprising: a. an a.c. power source, and a power switch, b. a magnetron having an anode electrode and a cathode electrode with a filament, c. a high voltage transformer having a primary winding connected to said a.c. power source through the power switch, a secondary winding for high operating voltage connected to said magnetron and a third winding for heating voltage connected to the filament of said magnetron, d. a half-wave rectifier connected to said secondary winding through a capacitor and coupled in reversed-parallel connection with said magnetron, and a surge-voltage absorber comprising a rectifying diode and a capacitor with a parallel resistor and coupled in parallel relation with said magnetron so as to absorb abnormal voltage appearing with the same polarity in said magnetron, whereby the magnetron can be energized upon closing of said power switch.
Claim 9
Dependent Claim
141 words
A magnetron operating circuit comprising: a. an a.c. power source, and a power switch, b. a magnetron having an anode electrode and a cathode electrode with a filament, c. a high voltage transformer having a primary winding connected to said a.c. power source through the power switch, a secondary winding for high operating voltage connected to said magnetron and a third winding for heating voltage connected to the filament of said magnetron, d. a half-wave rectifier connected to said secondary winding through a capacitor and coupled in reversed-parallel connection with said magnetron, and a surge-voltage absorber comprising a rectifying diode and a capacitor with a parallel resistor and coupled in parallel relation with said magnetron so as to absorb abnormal voltage appearing with the same polarity in said magnetron, whereby the magnetron can be energized upon closing of said power switch.
Claim 10
Dependent Claim
26 words
The magnetron operating circuit as claimed in claim 7, wherein said surge-voltage absorber is connected across the terminals of said secondary winding of said high-voltage transformer.
Claim 11
Dependent Claim
29 words
The magnetron operating circuit as claimed in claim 7, further comprising a resistor connected across said half-wave rectifier so as to discharge electric charges remaining in the operating circuit.
Claim 12
Dependent Claim
138 words
A magnetron operating circuit comprising: a. an a.c. power source, b. a pair of magnetrons each having an anode and a cathode with a filament, a first pair of like electrodes being interconnected, c. a high voltage transformer having a primary winding connected to said a.c. power source and a secondary winding connected between the other like electrodes of said pair of magnetrons, d. a first and second half-wave rectifier connected in parallel with separate magnetrons in a manner that each magnetron is operated by alternate half-cycles of said a.c. power source, and a pair of surge-voltage absorbers, each of said absorbers comprising a rectifier diode connected in series with a parallel circuit of a capacitor and resistor, and said absorbers being connected in reverse parallel connection with separate half-wave rectifiers, whereby the circuit can operate two magnetrons.
Claim 13
Dependent Claim
138 words
A magnetron operating circuit comprising: a. an a.c. power source, b. a pair of magnetrons each having an anode and a cathode with a filament, a first pair of like electrodes being interconnected, c. a high voltage transformer having a primary winding connected to said a.c. power source and a secondary winding connected between the other like electrodes of said pair of magnetrons, d. a first and second half-wave rectifier connected in parallel with separate magnetrons in a manner that each magnetron is operated by alternate half-cycles of said a.c. power source, and a pair of surge-voltage absorbers, each of said absorbers comprising a rectifier diode connected in series with a parallel circuit of a capacitor and resistor, and said absorbers being connected in reverse parallel connection with separate half-wave rectifiers, whereby the circuit can operate two magnetrons.
Claim 14
Dependent Claim
25 words
The magnetron operating circuit as claimed in claim 10, wherein said high voltage transformer is a leakage transformer so as to obtain constant current operation.
Claim 15
Dependent Claim
32 words
The magnetron operating circuit as claimed in claim 10, said high voltage transformer has further a pair of third windings, each of which is connected to said filament of a separate magnetron.
Claim 16
Dependent Claim
148 words
A magnetron operating circuit for energizing a magnetron from an a.c. source, comprising: a. a magnetron having an anode and a cathode, b. a high voltage transformer having a primary winding adapted to be connected to said a.c. source, and a secondary winding, c. a first capacitor, d. means connecting said first capacitor and secondary winding in series between the cathode and anode of said magnetron in that order, e. a first rectifier having an anode connected to the cathode of said magnetron, and a cathode connected to the anode of said magnetron, f. and a surge voltage absorber coupled in parallel with said secondary winding, said surge voltage absorber comprising the series connection of a second rectifier with the parallel circuit of a second capacitor and a resistor, said second rectifier being poled with its cathode connected to the junction of said first capacitor and secondary winding.
Claim 17
Dependent Claim
148 words
A magnetron operating circuit for energizing a magnetron from an a.c. source, comprising: a. a magnetron having an anode and a cathode, b. a high voltage transformer having a primary winding adapted to be connected to said a.c. source, and a secondary winding, c. a first capacitor, d. means connecting said first capacitor and secondary winding in series between the cathode and anode of said magnetron in that order, e. a first rectifier having an anode connected to the cathode of said magnetron, and a cathode connected to the anode of said magnetron, f. and a surge voltage absorber coupled in parallel with said secondary winding, said surge voltage absorber comprising the series connection of a second rectifier with the parallel circuit of a second capacitor and a resistor, said second rectifier being poled with its cathode connected to the junction of said first capacitor and secondary winding.
Claim 18
Dependent Claim
14 words
The magnetron operating circuit of claim 13, wherein said transformer is a leakage transformer.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-07 | 1978-04-08 | 1978-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-07 | 1982-04-08 | 1982-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-07 | 1986-04-08 | 1986-10-08 | $7700.00 | Window Closed / Lapsed |