Patent US4450577A successfully refreshed from Google Patents.
US4450577A
Expired / Lapsed
US
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X-Ray apparatus
Assignee: Toshiba Corp
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Filing: 1982-09-14
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Granted: 1984-05-22
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Expires: 2002-09-14
Abstract
Abstract An X-ray apparatus is disclosed which comprises an X-ray tube, a high voltage generating circuit for applying a high voltage between the anode and the cathode of the X-ray tube, a filament heating circuit for heating a filament of the X-ray tube, first switching element connected between one terminal of said filament and the negative bus of said high voltage generating circuit, second switching element connected between the other terminal of said filament and the negative bus of said high voltage generating circuit and an inverter circuit for alternately switching said first and second switching elements at a given period to switch the tube current paths.
Inventors
- 👤 Hideki Sato
- 👤 Hiroshi Asahina
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:03
CPC Classifications
H; H05; H05G; H05G1/00; H05G1/08; H05G1/26; H05G1/30; H05G1/34; H05G1/32
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
105 words
An X-ray apparatus comprising: an X-ray tube; a high voltage generating circuit for applying a high voltage between the anode and the cathode of said X-ray tube; a direct current filament heating circuit for heating a filament of said X-ray tube; first switching element connected between one terminal of said filament and the negative bus of said high voltage generating circuit; second switching element connected between the other terminal of said filament and the negative bus of said high voltage generating circuit; and switching circuit means for alternately switching said first and second switching elements at a given period to switch the tube current paths.
Claim 2
Dependent Claim
105 words
An X-ray apparatus comprising: an X-ray tube; a high voltage generating circuit for applying a high voltage between the anode and the cathode of said X-ray tube; a direct current filament heating circuit for heating a filament of said X-ray tube; first switching element connected between one terminal of said filament and the negative bus of said high voltage generating circuit; second switching element connected between the other terminal of said filament and the negative bus of said high voltage generating circuit; and switching circuit means for alternately switching said first and second switching elements at a given period to switch the tube current paths.
Claim 3
Dependent Claim
39 words
An X-ray apparatus according to claim 1, further including, impedance means for preventing an instable state at the time of the alternate switching of said first and second switches, said impedance means being connected across said first switching element.
Claim 4
Dependent Claim
25 words
An X-ray apparatus according to claim 1 or 2, wherein said first switching element is a diode and said second switching element is a transistor.
Claim 5
Dependent Claim
14 words
An X-ray apparatus according to claim 2, wherein said impedance means is a capacitor.
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) | 1987-05-22 | 1987-11-21 | 1988-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-22 | 1991-11-21 | 1992-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-22 | 1995-11-21 | 1996-05-22 | $7700.00 | Window Closed / Lapsed |